Tracked vehicle

ABSTRACT

A tracked vehicle, such as tracked carrier to carry and enable use of work equipment (e.g., a crane, an aerial work platform, a drill rig, etc.) on various terrains, is provided. The tracked vehicle may comprise a frame comprising an equipment mounting area for mounting work equipment above the frame. The frame may comprise a pair of side rails that have a spacing in a widthwise direction of the tracked vehicle which corresponds to a standard truck frame side rail spacing (e.g., 34 inches). An operator cabin comprises a seating area which may comprise a single seat for an operator or a first seat for the operator and a second seat for a second person next to the operator. At least part of a power plant of the tracked vehicle may be mounted above the frame and behind the operator cabin. The tracked vehicle comprises a plurality of track assemblies for traction of the tracked vehicle.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/342,143 filed Jul. 28, 2014, which is a national stage ofInternational Application No. PCT/CA2012/000815 filed Aug. 30, 2012,which claims the benefit of U.S. Provisional Patent Application No.61/542,551 filed on Oct. 3, 2011 and U.S. Provisional Patent ApplicationNo. 61/529,639 filed on Aug. 31, 2011. This application is also acontinuation of U.S. patent application Ser. No. 14/194,270 filed Feb.28, 2014, now U.S. Pat. No. 9,604,679, which is a continuation ofInternational Application No. PCT/CA2012/000815 filed Aug. 30, 2012,which claims the benefit of U.S. Provisional Patent Application No.61/542,551 filed on Oct. 3, 2011 and U.S. Provisional Patent ApplicationNo. 61/529,639 filed on Aug. 31, 2011. All of the above-identifiedapplications and patents are hereby incorporated by reference.

FIELD OF THE INVENTION

The invention relates to tracked vehicles designed to travel on variousterrains, including rugged terrain, and, in particular, to trackedutility vehicles carrying work equipment.

BACKGROUND

One type of tracked vehicle is a tracked utility vehicle, sometimesreferred to as a “tracked carrier” or “tracked equipment carrier”vehicle, which carries and enables use of work equipment, such as acrane, an aerial device, a drill rig, a digger derrick, and/or any otherindustrial apparatus, on various terrains, including rugged terrain(e.g., with mud, steep hills, swamps, rocks, mud, and/or snow).

It is often desirable for a tracked utility vehicle to have a tarryingcapacity as large as possible but yet be sized such that the vehicle canfit a public road infrastructure. For example, it may be desirable thatthe vehicle be low enough to fit below an underpass or otherwise respecta vehicle height limit of the public road infrastructure (e.g., whentransported on a truck's deck trailer). This typically imposes certainlimitations on components of the vehicle. For instance, this may limit asize of an operator cabin of the vehicle, to avoid interference with thework equipment carried by the vehicle.

The work equipment carried by a tracked utility vehicle is normallymounted to the vehicle's frame. This can often present issues orchallenges. For example, the work equipment is often designed to beinstalled on a truck's frame. Since the tracked utility vehicle's frameis typically very different from a truck's frame, the work equipmentcannot be mounted as readily to the tracked utility vehicle's frame thanto a truck's frame. Rather, modifications may have to be made to thework equipment and/or to the tracked utility vehicle to allow the workequipment to be installed on the tracked utility vehicle's frame. Forinstance, in some cases, an intermediate support structure may need tobe installed between the work equipment and the tracked utilityvehicle's frame to support and anchor the work equipment.

Each track assembly of a tracked utility vehicle comprises an endlesstrack disposed around a set of wheels and engaging the ground togenerate traction. Installing the endless track around the set of wheelscan sometimes be difficult. For instance, in some case, the endlesstrack's inner side may have guide projections which may interfere withsome of the wheels during installation of the track around the set ofwheels. Also, tension in the endless track may be maintained by anindependent tensioner (e.g., a hydraulic accumulator and cylinder or aspring-loaded actuator) which may cause certain issues (e.g.,difficulties in maintaining constant tension over displacement of thecylinder or actuator).

Challenges similar to those discussed above in respect of a trackedutility vehicle may be encountered in other types of industrial trackedvehicles.

Accordingly, there is a need for improvements in tracked utilityvehicles and other tracked vehicles.

SUMMARY OF THE INVENTION

In accordance with an aspect of the invention, there is provided atracked vehicle. The tracked vehicle comprises a chassis comprising aframe extending along a longitudinal direction of the tracked vehicle.The frame comprises an equipment mounting area for mounting workequipment above the frame. The tracked vehicle comprises an operatorcabin mounted to the frame. The tracked vehicle also comprises a powerplant mounted to the frame and comprising a prime mover. At least partof the power plant is mounted above the frame and behind the operatorcabin. The tracked vehicle comprises a plurality of track assemblies fortraction of the tracked vehicle. A first one of the track assemblies ison a first lateral side of the tracked vehicle and a second one of thetrack assemblies is on a second lateral side of the tracked vehicle.Each track assembly of the plurality of track assemblies is mounted tothe frame and comprises: (i) a plurality of wheels including: a drivewheel; an end wheel spaced apart from the drive wheel in thelongitudinal direction of the tracked vehicle; and a plurality ofsupport wheels arranged in an inline configuration between the drivewheel and the end wheel; and (ii) an endless track disposed around theplurality of wheels for engaging the ground. The endless track comprisesa top run extending between the drive wheel and the end wheel over thesupport wheels and a ground-engaging bottom run extending under thesupport wheels. The drive wheel is in driving engagement with theendless track to impart motion to the endless track.

In accordance with another aspect of the invention, there is provided atracked vehicle. The tracked vehicle comprises a chassis comprising aframe extending along a longitudinal direction of the tracked vehicle.The frame comprises an equipment mounting area for mounting workequipment above the frame. The tracked vehicle comprises an operatorcabin mounted to the frame. The operator cabin comprises a seating areafor allowing an operator to sit. The seating area defines a first seatposition and a second seat position along a widthwise direction of thetracked vehicle. The tracked vehicle also comprises a power plantmounted to the frame and comprising a prime mover. The tracked vehiclecomprises a plurality of track assemblies for traction of the trackedvehicle. A first one of the track assemblies is on a first lateral sideof the tracked vehicle and a second one of the track assemblies is on asecond lateral side of the tracked vehicle. Each track assembly of theplurality of track assemblies is mounted to the frame and comprises: (i)a plurality of wheels including: a drive wheel; an end wheel spacedapart from the drive wheel in the longitudinal direction of the trackedvehicle; and a plurality of support wheels arranged in an inlineconfiguration between the drive wheel and the end wheel; and (ii) anendless track disposed around the plurality of wheels for engaging theground. The endless track comprises a top run extending between thedrive wheel and the end wheel over the support wheels and aground-engaging bottom run extending under the support wheels. The drivewheel is in driving engagement with the endless track to impart motionto the endless track. The tracked vehicle, with the work equipmentmounted to the frame, respects a vehicle height limit for travel on apublic road infrastructure.

In accordance with another aspect of the invention, there is provided atracked vehicle. The tracked vehicle comprises a chassis comprising aframe extending along a longitudinal direction of the tracked vehicle.The frame comprises an equipment mounting area for mounting workequipment above the frame. The tracked vehicle comprises an operatorcabin mounted to the frame. The operator cabin comprises a first seatfor allowing an operator to sit and a second seat for allowing a secondperson to sit next to the operator in a widthwise direction of thetracked vehicle. The tracked vehicle also comprises a power plantmounted to the frame and comprising a prime mover. The tracked vehiclecomprises a plurality of track assemblies for traction of the trackedvehicle. A first one of the track assemblies is on a first lateral sideof the tracked vehicle and a second one of the track assemblies is on asecond lateral side of the tracked vehicle. Each track assembly of theplurality of track assemblies is mounted to the frame and comprises: (i)a plurality of wheels including: a drive wheel; an end wheel spacedapart from the drive wheel in the longitudinal direction of the trackedvehicle; and a plurality of support wheels arranged in an inlineconfiguration between the drive wheel and the end wheel; and (ii) anendless track disposed around the plurality of wheels for engaging theground. The endless track comprises a top run extending between thedrive wheel and the end wheel over the support wheels and aground-engaging bottom run extending under the support wheels. The drivewheel is in driving engagement with the endless track to impart motionto the endless track.

In accordance with another aspect of the invention, there is provided atracked vehicle. The tracked vehicle comprises a chassis comprising aframe extending along a longitudinal direction of the tracked vehicle.The frame comprises an equipment mounting area for mounting workequipment above the frame. The tracked vehicle comprises an operatorcabin mounted to the frame. The operator cabin comprises a seating areafor allowing an operator to sit. The seating area defines a first seatposition and a second seat position along a widthwise direction of thetracked vehicle. The operator cabin comprises a roof defining a heightof the tracked vehicle. The height of the tracked vehicle is no morethan 2.8 m. The tracked vehicle also comprises a power plant mounted tothe frame and comprising a prime mover. The tracked vehicle comprises aplurality of track assemblies for traction of the tracked vehicle. Afirst one of the track assemblies is on a first lateral side of thetracked vehicle and a second one of the track assemblies is on a secondlateral side of the tracked vehicle. Each track assembly of theplurality of track assemblies is mounted to the frame and comprises: (i)a plurality of wheels including: a drive wheel; an end wheel spacedapart from the drive wheel in the longitudinal direction of the trackedvehicle; and a plurality of support wheels arranged in an inlineconfiguration between the drive wheel and the end wheel; and (ii) anendless track disposed around the plurality of wheels for engaging theground. The endless track comprises a top run extending between thedrive wheel and the end wheel over the support wheels and aground-engaging bottom run extending under the support wheels. The drivewheel is in driving engagement with the endless track to impart motionto the endless track.

In accordance with another aspect of the invention, there is provided atracked vehicle. The tracked vehicle comprises a chassis comprising aframe extending along a longitudinal direction of the tracked vehicle.The frame comprises an equipment mounting area for mounting workequipment above the frame. The tracked vehicle comprises an operatorcabin mounted to the frame. The operator cabin comprises a seating areafor allowing an operator to sit and a user interface for enabling theoperator to control the tracked vehicle. The user interface comprises anaccelerator for controlling a speed of the tracked vehicle and asteering device for steering the tracked vehicle. The operator cabin isconfigurable in a plurality of cabin configurations including: a firstcabin configuration in which the operator sits in a first seat positionof the seating area along a widthwise direction of the tracked vehicleand the steering device is in a first steering device position along thewidthwise direction of the tracked vehicle; and a second cabinconfiguration in which the operator sits in a second seat position ofthe seating area along the widthwise direction of the tracked vehicleand the steering device is in a second steering device position alongthe widthwise direction of the tracked vehicle. The tracked vehicle alsocomprises a power plant mounted to the frame and comprising a primemover. The tracked vehicle comprises a plurality of track assemblies fortraction of the tracked vehicle. A first one of the track assemblies ison a first lateral side of the tracked vehicle and a second one of thetrack assemblies is on a second lateral side of the tracked vehicle.Each track assembly of the plurality of track assemblies is mounted tothe frame and comprises: (i) a plurality of wheels including: a drivewheel; an end wheel spaced apart from the drive wheel in thelongitudinal direction of the tracked vehicle; and a plurality ofsupport wheels arranged in an inline configuration between the drivewheel and the end wheel; and (ii) an endless track disposed around theplurality of wheels for engaging the ground. The endless track comprisesa top run extending between the drive wheel and the end wheel over thesupport wheels and a ground-engaging bottom run extending under thesupport wheels. The drive wheel is in driving engagement with theendless track to impart motion to the endless track.

In accordance with another aspect of the invention, there is provided atracked vehicle. The tracked vehicle comprises a chassis comprising aframe extending along a longitudinal direction of the tracked vehicle.The frame comprises an equipment mounting area for mounting workequipment above the frame. The tracked vehicle comprises an operatorcabin mounted to the frame. The operator cabin comprises a seating areafor allowing an operator to sit and a user interface for enabling theoperator to control the tracked vehicle. The user interface comprises anaccelerator for controlling a speed of the tracked vehicle and asteering device for steering the tracked vehicle. The operator cabin isconfigurable in a plurality of cabin configurations including: a firstcabin configuration in which the operator sits in a first seat positionof the seating area along a widthwise direction of the tracked vehicleand the steering device is in a first steering device position along thewidthwise direction of the tracked vehicle; and a second cabinconfiguration in which the operator sits in a second seat position ofthe seating area along the widthwise direction of the tracked vehicleand the steering device is in a second steering device position alongthe widthwise direction of the tracked vehicle. The tracked vehicle alsocomprises a power plant mounted to the frame and comprising a primemover. The tracked vehicle comprises a plurality of track assemblies fortraction of the tracked vehicle. A first one of the track assemblies ison a first lateral side of the tracked vehicle and a second one of thetrack assemblies is on a second lateral side of the tracked vehicle.Each track assembly of the plurality of track assemblies is mounted tothe frame and comprises a plurality of wheels including: a drive wheel;an end wheel spaced apart from the drive wheel in the longitudinaldirection of the tracked vehicle; and a plurality of support wheelsarranged in an inline configuration between the drive wheel and the endwheel. Each support wheel occupies a majority of a height of the trackassembly and comprises a first support wheel member rotatable on an axleof the support wheel and having a circumference of the support wheel anda second support wheel member rotatable on the axle of the support wheeland having the circumference of the support wheel. The second supportwheel member is installable in and removable from the track assemblyseparately from the first support wheel member. The track assembly alsocomprises an endless track disposed around the plurality of wheels forengaging the ground. The endless track comprises a top run extendingbetween the drive wheel and the end wheel over the support wheels and aground-engaging bottom run extending under the support wheels. The drivewheel is in driving engagement with the endless track to impart motionto the endless track.

In accordance with another aspect of the invention, there is provided atracked vehicle. The tracked vehicle comprises a chassis comprising aframe extending along a longitudinal direction of the tracked vehicle.The frame comprises a pair of side rails spaced apart in a widthwisedirection of the tracked vehicle for mounting work equipment carried bythe tracked vehicle to the side rails. A spacing of the side rails inthe widthwise direction of the tracked vehicle corresponds to a standardtruck frame side rail spacing. The tracked vehicle comprises an operatorcabin mounted to the frame. The tracked vehicle also comprises a powerplant mounted to the frame and comprising a prime mover. The trackedvehicle comprises a plurality of track assemblies for traction of thetracked vehicle. A first one of the track assemblies is on a firstlateral side of the tracked vehicle and a second one of the trackassemblies is on a second lateral side of the tracked vehicle. Eachtrack assembly of the plurality of track assemblies is mounted to theframe and comprises: (i) a plurality of wheels including: a drive wheel;an end wheel spaced apart from the drive wheel in the longitudinaldirection of the tracked vehicle; and a plurality of support wheelsarranged in an inline configuration between the drive wheel and the endwheel; and (ii) an endless track disposed around the plurality of wheelsfor engaging the ground. The endless track comprises a top run extendingbetween the drive wheel and the end wheel over the support wheels and aground-engaging bottom run extending under the support wheels. The drivewheel is in driving engagement with the endless track to impart motionto the endless track.

In accordance with another aspect of the invention, there is provided atracked vehicle. The tracked vehicle comprises a chassis comprising aframe extending along a longitudinal direction of the tracked vehicle.The frame comprises a pair of side rails spaced apart in a widthwisedirection of the tracked vehicle for mounting work equipment carried bythe tracked vehicle to the side rails. A spacing of the side rails inthe widthwise direction of the tracked vehicle being no greater than 34inches. The tracked vehicle also comprises a power plant mounted to theframe and comprising a prime mover. The tracked vehicle comprises anoperator cabin mounted to the frame. The tracked vehicle comprises aplurality of track assemblies for traction of the tracked vehicle. Afirst one of the track assemblies is on a first lateral side of thetracked vehicle and a second one of the track assemblies is on a secondlateral side of the tracked vehicle. Each track assembly of theplurality of track assemblies is mounted to the frame and comprises: (i)a plurality of wheels including: a drive wheel; an end wheel spacedapart from the drive wheel in the longitudinal direction of the trackedvehicle; and a plurality of support wheels arranged in an inlineconfiguration between the drive wheel and the end wheel; and (ii) anendless track disposed around the plurality of wheels for engaging theground. The endless track comprises a top run extending between thedrive wheel and the end wheel over the support wheels and aground-engaging bottom run extending under the support wheels. The drivewheel is in driving engagement with the endless track to impart motionto the endless track.

In accordance with another aspect of the invention, there is provided atracked vehicle. The tracked vehicle comprises a chassis comprising aframe extending along a longitudinal direction of the tracked vehicle.The frame comprises an upper frame structure including a pair of siderails spaced apart in a widthwise direction of the tracked vehicle formounting work equipment carried by the tracked vehicle to the siderails. The frame also comprises a lower frame structure below the upperframe structure. The frame defines a vertical gap between the upperframe structure and the lower frame structure. The tracked vehicle alsocomprises a power plant mounted to the frame and comprising a primemover. The tracked vehicle comprises an operator cabin mounted to theframe. The tracked vehicle comprises a plurality of track assemblies fortraction of the tracked vehicle. A first one of the track assemblies ison a first lateral side of the tracked vehicle and a second one of thetrack assemblies is on a second lateral side of the tracked vehicle.Each track assembly of the plurality of track assemblies is mounted tothe frame and comprises: (i) a plurality of wheels including: a drivewheel; an end wheel spaced apart from the drive wheel in thelongitudinal direction of the tracked vehicle; and a plurality ofsupport wheels arranged in an inline configuration between the drivewheel and the end wheel; and (ii) an endless track disposed around theplurality of wheels for engaging the ground. The endless track comprisesa top run extending between the drive wheel and the end wheel over thesupport wheels and a ground-engaging bottom run extending under thesupport wheels. The drive wheel is in driving engagement with theendless track to impart motion to the endless track.

In accordance with another aspect of the invention, there is provided atracked vehicle. The tracked vehicle comprises a chassis comprising aframe extending along a longitudinal direction of the tracked vehicle.The tracked vehicle also comprises a power plant mounted to the frameand comprising a prime mover and a hydraulic drive system connected tothe prime mover. The tracked vehicle comprises an operator cabin mountedto the frame. The tracked vehicle comprises a plurality of trackassemblies for traction of the tracked vehicle. A first one of the trackassemblies is on a first lateral side of the tracked vehicle and asecond one of the track assemblies is on a second lateral side of thetracked vehicle. Each track assembly of the plurality of trackassemblies is mounted to the frame and comprises: (i) a plurality ofwheels including a drive wheel; an end wheel spaced apart from the drivewheel in the longitudinal direction of the tracked vehicle; and aplurality of support wheels arranged in an inline configuration betweenthe drive wheel and the end wheel; (ii) an endless track disposed aroundthe plurality of wheels for engaging the ground; and iii) a tracktensioner for maintaining tension in the endless track. The tracktensioner comprises a hydraulic actuator hydraulically connected to thehydraulic drive system. The endless track comprises a top run extendingbetween the drive wheel and the end wheel over the support wheels and aground-engaging bottom run extending under the support wheels. The drivewheel is in driving engagement with the endless track to impart motionto the endless track.

In accordance with another aspect of the invention, there is provided atracked vehicle. The tracked vehicle comprises a chassis comprising aframe extending along a longitudinal direction of the tracked vehicle.The tracked vehicle also comprises a power plant mounted to the frameand comprising a prime mover. The tracked vehicle comprises a pluralityof track assemblies for traction of the tracked vehicle. A first one ofthe track assemblies is on a first lateral side of the tracked vehicleand a second one of the track assemblies is on a second lateral side ofthe tracked vehicle. Each track assembly of the plurality of trackassemblies is mounted to the frame and comprises a plurality of wheelsincluding: a drive wheel; a rear wheel spaced apart from the drive wheelin the longitudinal direction of the tracked vehicle; and a plurality ofsupport wheels arranged in an inline configuration between the drivewheel and the end wheel.

The rear wheel and a rearmost one of the support wheels overlap in thelongitudinal direction of the tracked vehicle. The track assembly alsocomprises an endless track disposed around the plurality of wheels forengaging the ground. The endless track comprises a top run extendingbetween the drive wheel and the end wheel over the support wheels and aground-engaging bottom run extending under the support wheels. The drivewheel is in driving engagement with the endless track to impart motionto the endless track.

These and other aspects of the invention will now become apparent tothose of ordinary skill in the art upon review of the followingdescription of embodiments of the invention in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

A detailed description of embodiments of the invention is providedbelow, by way of example only, with reference to the accompanyingdrawings, in which:

FIGS. 1 to 6 show a first perspective view, a second perspective view, aside view, a front view, a rear view, and a top view of an example of atracked vehicle equipped with work equipment in accordance with anembodiment of the invention;

FIGS. 7 to 13 show a first perspective view, a second perspective view,a side view, a front view, a rear view, a top view, and a bottom view ofthe tracked vehicle without the work equipment;

FIGS. 14 to 18 show a perspective view, a side view, a top view, a frontview, and a rear view of a chassis including a frame and trackassemblies of the tracked vehicle;

FIGS. 19 to 25 show a perspective view, a side view, a top view, abottom view, a front view, a rear view, and a cross-sectional view ofthe frame and the track assemblies without endless tracks of the trackassemblies;

FIGS. 26 to 28 show examples of attachment devices which secure the workequipment to the frame of the tracked vehicle;

FIGS. 29 and 30 show a top view of an inner side, and a cross-sectionalview, of an endless track in accordance with an embodiment of theinvention;

FIGS. 31 and 32 show a perspective view of a ground-engaging outer side,and a perspective view of an inner side, of an endless track inaccordance with another embodiment of the invention;

FIGS. 33 and 34 show front and rear perspective views of a power plantof the tracked vehicle with panels of a housing of the power plantremoved;

FIGS. 35 and 36 show cross-sectional views of a support wheel of a trackassembly with and without the endless track;

FIGS. 37 and 38 show a perspective view and a cross-sectional view of atrack tensioner in relation to wheels of a track assembly;

FIGS. 39 and 40 show a perspective view and a cross-sectional view of asupport wheel of a track assembly in accordance with another embodimentof the invention;

FIG. 41 shows an operator cabin of the tracked vehicle configured in aone-person configuration;

FIG. 42 shows the operator cabin in the one-person configuration with aseat and components of a user interface removed;

FIG. 43 shows the operator cabin configured in a two-personconfiguration;

FIG. 44 shows the operator cabin in the two-person configuration withseats and components of the user interface removed;

FIG. 45 shows components of the user interface connected to othercomponents of the tracked vehicle;

FIG. 46 shows a seat support and part of a user interface support of theoperator cabin;

FIG. 47 shows the seat support and the user interface support of theoperator cabin; and

FIGS. 48 to 50 show track tensioners of the track assemblieshydraulically connected to a hydraulic drive system of the trackedvehicle.

In the drawings, embodiments of the invention are illustrated by way ofexample. It is to be expressly understood that the description anddrawings are only for the purpose of illustrating certain embodiments ofthe invention and are an aid for understanding. They are not intended tobe a definition of the limits of the invention.

DETAILED DESCRIPTION OF EMBODIMENTS

FIGS. 1 to 13 show an example of a tracked utility vehicle 10 inaccordance with an embodiment of the invention. The tracked utilityvehicle 10 is designed to carry and enable use of work equipment 41,which includes one or more work implements such as, for example, acrane, a ladder, an aerial device, an aerial work platform, a lift, adrill rig, a digger derrick, a material handler, and/or any otherindustrial apparatus, on various terrains, including rugged terrain(e.g., with mud, steep hills, swamps, rocks, mud, and/or snow). Thistype of vehicle can sometimes be referred to as a “tracked carrier” or“tracked equipment carrier” vehicle.

The tracked utility vehicle 10 has a length L_(v), a width W_(v), and aheight H_(v) (measured without taking into account the work equipment41). These dimensions may allow the vehicle 10 to have a large payloadcapacity while being able to be used in a public road infrastructure.For example, in some embodiments, the length L_(v) may be at least 5 m,such as between 5 m and 10 m, in some cases between 6 m and 9 m, and insome cases between 7 m and 8 m; the width W_(v) may be at least 2 m,such as between 2 m and 5 m, in some cases between 2.5 m and 4.5 m, andin some cases between 3 m and 4 m; and the height H_(v) may be no morethan 4 m, in some cases no more than 3.5 m, and in some cases no morethan 3 m. The length L_(v), width W_(v), and height H_(v) may take onvarious other values in other embodiments.

The tracked utility vehicle 10 has a payload capacity which carp bequite larger. For example, in some embodiments, the payload capacity ofthe vehicle 10 may be at least 10000 lbs (about 4536 kg), in some casesat least 15000 lbs (about 6804 kg), in some cases at least 20000 lbs(about 9072 kg), in some cases at least 30000 lbs (about 13608 kg), andin some cases at least 40000 lbs (18144 kg). The payload capacity maytake on various other values in other embodiments.

In this embodiment, the tracked utility vehicle 10 comprises a chassis12, a power plant 14, a plurality of track assemblies 16 ₁, 16 ₂, and anoperator cabin 20. The vehicle 10 has a longitudinal axis 59 defining alongitudinal direction of the vehicle 10 (i.e., a direction generallyparallel to its longitudinal axis 59) and transversal directions (i.e.,directions transverse to its longitudinal axis 59), including awidthwise direction (i.e., a lateral direction generally perpendicularto its longitudinal axis 59). The vehicle 10 also has a height directionwhich is normal to both its longitudinal direction and its widthwisedirection.

a) Power Plant

The power plant 14 generates power to move the tracked utility vehicle10. To that end, the power plant 14 comprises a prime mover 17. Forexample, the prime mover 17 may comprise an internal combustion engineand/or one or more other types of motors (e.g., electric motors, etc.)for generating motive power to move the vehicle 10.

The power plant 14 is in a driving relationship with each of the trackassemblies 16 ₁, 16 ₂. That is, power derived from the power plant 14 istransmitted to each of the track assemblies 16 ₁, 16 ₂ in order to drivethe track assemblies 16 ₁, 16 ₂. In this embodiment, with additionalreference to FIG. 33, power from the power plant 14 is transmitted tothe track assemblies 16 ₁, 16 ₂ via a hydraulic drive system 21. Forinstance, in this example, the hydraulic drive system 21 comprises, foreach of the track assemblies 16 ₁, 16 ₂, a hydraulic pump 26 driven bythe prime mover 17 and connected to a hydraulic motor (not shown) whichdrives that track assembly. Power from the power plant 14 may betransmitted to the track assemblies 16 ₁, 16 ₂ in various other ways inother embodiments.

In this embodiment, the power plant 14 includes a housing 46 whichhouses the prime mover 17 and other components of the power plant 14.More particularly, in this embodiment, the housing 46 houses: hydrauliccomponents including each hydraulic pump 26 of the hydraulic drivesystem 21 and a hydraulic fluid reservoir; a cooling system for coolingthe prime mover 17 and hydraulic fluid of the hydraulic drive system 21;batteries; components of an exhaust system; pipes; and cables. Othercomponents of the power plant 14 may be housed in the housing 46 inother embodiments.

The housing 46 and the components of the power plant 14 that it housesare mounted on top of the chassis 12. More particularly, in thisembodiment, the housing 46 comprises a back housing portion 47 ₁ whichhouses a first portion of the power plant 14 and is located above thechassis 12 behind the operator cabin 20 and a side housing portion 47 ₂which houses a second portion of the power plant 14 and is located abovethe chassis 12 on a right side of the operator cabin 20. Thus, in thisembodiment, the housing 46 has a generally L-shaped configuration thatextends behind and next to the operator cabin 20, with the back housingportion 47 ₁ being elongated in the widthwise direction of the vehicle10 and the side housing portion 47 ₂ being elongated in the longitudinaldirection of the vehicle 10.

Mounting of the housing 46 and the components of the power plant 14 thatit houses above the chassis 12 may facilitate installation and servicingof the power plant 14. For example, maintenance or other servicingactivities may be performed by accessing components of the power plant14 without being obstructed by the work equipment 41.

Also, components of the power plant 14, including the prime mover 17,the hydraulic pumps of the hydraulic drive system 21, and the housing46, may secured to one another to constitute a “power plant module” thatcan be installed on and removable from the chassis 12 together as aunit. This may allow the tracked utility vehicle 10 to be easilyequipped with a particular one of a plurality of different power plantmodules during manufacturing of the vehicle 10 depending on anapplication or environment in which the vehicle 10 will be used. Forexample, in some embodiments, the plurality of different power plantmodules may comprise different types of prime movers. For instance, insome cases, the different types of prime movers may be different typesof internal combustion engines, such as different types of engines thatconform to requirements of different engine tiers (e.g., an engineconforming to requirements of a T3 engine tier and an engine conformingto requirements of a T4 engine tier). In such examples ofimplementation, a controller controlling the prime mover 17 (e.g., anengine control unit (ECU) may comprise software that can control thedifferent types of engines and receives an input indicating a particulartype of engine to which the prime mover 17 corresponds to control itaccordingly.

Furthermore, mounting of the housing 46 and the components of the powerplant 14 that it houses above the chassis 12 may allow the height H_(v)of the tracked utility vehicle 10 to be kept small. This may bebeneficial in various cases.

For example, in this embodiment, the operator cabin 20 can seat twoindividuals (i.e., can comprise two seats) as further discussed lateron, and the tracked utility vehicle 10 carrying the work equipment 41can travel on a public road infrastructure. The vehicle 10 may travel onthe public road infrastructure by self-propulsion or by beingtransported on another vehicle (e.g., on a flatbed truck). The vehicle10 may therefore respect a vehicle height limit (i.e., a maximum vehicleheight allowable) for travel on the public road infrastructure. Thevehicle height limit is normally set by a government responsible for thepublic road infrastructure. For example, in some cases, the vehicleheight limit for travel on the public road infrastructure may be between13.5 feet (4.1 m) and 14 feet (4.3 m). The vehicle height limit fortravel on the public road infrastructure may have any other suitablevalue in other cases. An overall height H_(v-o) of the vehicle 10,measured with the work equipment 41 in a retracted nonworking state, maythus be designed taking into account the vehicle height limit and aheight of a trailer on which the vehicle 10 may be transported on thepublic road infrastructure. For example, if a trailer having a height of24 inches is expected to be used for transporting the vehicle 10, theoverall height H_(v-o) of the vehicle 10 may be no more than 11.5 feet(3.5 m) if the vehicle height limit is 13.5 feet or no more than 12 feet(3.7 m) if the vehicle height limit is 14 feet. As another example, if atrailer having a height of 18 inches is expected to be used fortransporting the vehicle 10, the overall height H_(v-o) of the vehicle10 may be no more than 12 feet if the vehicle height limit is 13.5 feetor no more than 12.5 feet if the vehicle height limit is 14 feet. Thus,in various examples the overall height H_(v-o) of the vehicle 10 may beno more than 12.5 feet, in some cases no more than 12 feet, and in somecases no more than 11.5 feet.

More particularly, in this embodiment, when the work equipment 41 is ina retracted nonworking state (i.e., a state in which it is retractedonto the vehicle 10 and not performing any work operation, as opposed toan extended working state in which it is extended outwardly from thevehicle 10 to perform a work operation), the work equipment 41 isarranged such that it extends frontward in the longitudinal direction ofthe vehicle 10 beyond a rear side 114 of the operator cabin 20. In thisexample of implementation, the work equipment 41 extends frontward inthe longitudinal direction of the vehicle 10 beyond a front side 112 ofthe operator cabin 20, next to a right side 116 ₂ of the operator cabin20, above the side housing portion 47 ₂. The work equipment 41 alsoextends above a roof 118 of the operator cabin 20. Mounting part of thepower plant 14, including the prime mover 17, on top of the chassis 12and behind the operator cabin 20 (e.g., as opposed to within an internalspace or “tub” defined by the chassis 12) allows the operator cabin 20,which can comprise two seats, to be low enough for installing the workequipment 41 in this manner. For example, in some embodiments, theheight H_(v) of the vehicle 10 to the roof 118 of the operator cabin 20may be no more than 2.8 m, in some cases no more than 2.7 m, and in somecases no more than 2.6 m. For instance, in this embodiment, the heightH_(v) of the vehicle 10 may be about 2.5 m.

As another example, the tracked utility vehicle 10, without the workequipment 41 installed thereon, may fit in a closed shipping containerfor transport (e.g., overseas). For instance, in some examples, amaximum height for a shipping container may be no more than 3 m, in somecases no more than 2.8 m, and in some cases no more than 2.6 m, and thevehicle 10 may fit in that shipping container.

As yet another example, keeping the height H_(v) of the tracked utilityvehicle 10 small may permit a vertical distance between a top of theoperator cabin 20 and the chassis 12 to be identical or similar to acorresponding distance in trucks to allow work equipment such as thework equipment 41 possibly designed primarily for mounting on trucks tobe easily mountable on the vehicle 10.

In addition to generating motive power to propel the tracked utilityvehicle 10, in some embodiments, the power plant 14 may power the workequipment 41 carried by the vehicle 10. For instance, in some cases, theprime mover 17 may be used to supply power to the work equipment 41. Inother cases, the power plant 14 may comprise another prime mover for tosupply power to the work equipment 41.

b) Track Assemblies

The track assemblies 16 ₁, 16 ₂ are used to propel the tracked utilityvehicle 10 on the ground. The track assembly 16 ₁ is on a first lateralside of the vehicle 10, while the track assembly 16 ₂ is on a secondlateral side of the vehicle 10. Each of the track assemblies 16 ₁, 16 ₂supports a portion of a weight of the vehicle 10 in use. In thisexample, the track assemblies 16 ₁, 16 ₂ are similarly configured andare disposed symmetrically relative to the chassis 12 and thus theportion of the weight of the vehicle 10 supported by each of the trackassemblies 16 ₁, 16 ₂ is about half of the weight of the vehicle 10. Inother examples, the portion of the weight of the vehicle 10 supported byeach of the track assemblies 16 ₁, 16 ₂ may be other than one-half ofthe weight of the vehicle 10.

With additional reference to FIGS. 14 to 18, in this embodiment, eachtrack assembly 16 _(i) comprises a plurality of wheels, which includes adrive wheel 24, an idler wheel 23, and a plurality of support wheels 28₁-28 ₄, and an endless track 22 disposed around the wheels 24, 23, 28₁-28 ₄. The track assembly 16 _(i) has a length L_(ta), a width W_(ta),and a height H_(ta). A longitudinal direction of the track assembly 16_(i) is generally parallel to the longitudinal direction of the trackedutility vehicle 10. The track assembly 16 _(i) also has transversaldirections, including a widthwise direction which is generally parallelto the widthwise direction of the tracked vehicle 10, and a heightdirection which is generally parallel to the height direction of thevehicle 10.

The endless track 22 engages the ground to provide traction. The endlesstrack 22 is disposed around the wheels 24, 23, 28 ₁-28 ₄ and includes atop run 40 and a bottom run 42. The top run 40 and the bottom run 42 ofthe endless track 22 are generally parallel to one another and extendalong the longitudinal direction of the tracked utility vehicle 10. Thetop run 40 of the endless track 22 is generally horizontal and has alength that is generally defined by the distance between the drive wheel24 and the idler wheel 23. The bottom run 42 of the endless track 22 isthat portion of the endless track 22 which is beneath the support wheels28 ₁-28 ₄ and which engages the ground. The bottom run 42 of the endlesstrack 22 has a length that is generally defined by the distance betweena frontmost one of the support wheel 28 ₁-28 ₄, in this case, thesupport wheel 28 ₁, and a rearmost one of the support wheel 28 ₁-28 ₄,in this case, the support wheel 28 ₄.

The drive wheel 24 is in a driven relationship with the power plant 14to impart movement of the endless track 22 in order to propel thevehicle 10 on the ground. The drive wheel 24 is rotatable about an axisof rotation which is transverse to the longitudinal direction of thevehicle 10 by power derived from the power plant 14 to impart movementof the endless track 22. In this embodiment, the drive wheel 24, whichis located in a front region of the chassis 12, comprises a sprocketthat engages the endless track 22. The drive wheel 24 may be configuredin various other ways in other embodiments.

The idler wheel 23 does not convert power derived from the power plant14 to motive force for movement of the endless track 22, but ratherguides the endless track 22 and maintains it under tension as it isdriven by the drive wheel 24. The idler wheel 23 is rotatable about anaxis of rotation which is transverse to the longitudinal direction ofthe tracked utility vehicle 10. In this embodiment, the idler wheel 23,which is located in a rear region of the chassis 12, may comprise asprocket or any other type of wheel that engages the endless track 22.

The support wheels 28 ₁-28 ₄ are arranged in an in-line configurationextending along the longitudinal direction of tracked utility vehicle 10and roll on the bottom run 42 of the endless track 22 as the vehicle 10moves on the ground. The support wheels 28 ₁-28 ₄ do not convert powerderived from the power plant 14 to motive force for movement of theendless track 22, but rather support and distribute onto the ground viathe endless track 22 the portion of the weight of the vehicle 10 that issupported by the track assembly 16 _(i). The support wheels 28 ₁-28 ₄may also maintain the shape and position of the endless track 22, aswell as keep the track 22 generally aligned with the general directionof vehicular movement.

Each of the support wheels 28 ₁-28 ₄ occupies most of the height H_(ta)of the track assembly 16 _(i). That is, each of the support wheels 28₁-28 ₄ has a diameter D_(sw) corresponding to at least half, in somecases at least two-thirds, and in some cases at least three-quarters ofthe height H_(ta) of the track assembly 16 _(i). In this case, thediameter D_(sw) of each of the support wheels 28 ₁-28 ₄ corresponds toabout 65% of the height H_(ta) of the track assembly 16 _(i). In someembodiments, the diameter D_(sw) of each of the support wheels 28 ₁-28 ₄may be such that the top run 40 of the endless track 22 can contact thesupport wheels 28 ₁-28 ₄ in use. In other embodiments, the supportwheels 28 ₁-28 ₄ may be made smaller such that there is no contactbetween the top run 40 of the endless track 22 and the support wheels 28₁-28 ₄ in use.

The support wheel 28 ₁-28 ₄ are carried by a plurality of wheel-carryingassemblies 50 ₁, 50 ₂ of the track assembly 16 _(i). Each of thewheel-carrying assemblies 50 ₁, 50 ₂ carries at least two of the supportwheels 28 ₁-28 ₄ and, since it is an assembly carrying wheels, will bereferred to as a “bogie”. More particularly, in this embodiment, thebogie 50 ₁ carries the support wheels 28 ₁, 28 ₂ and the bogie 50 ₂carries the support wheels 28 ₃, 28 ₄.

The bogie 50 ₁ comprises a link 70 interconnecting the support wheels 28₁, 28 ₂ and pivotable relative to the chassis 12 about a pivot 71 whichdefines a pivot axis. The link 70 is a connecting structure that mayhave any suitable form (e.g., a single member or a plurality of membersconnected to one another by one or more fasteners, welding, etc.). Thesupport wheels 28 ₁, 28 ₂ are rotatably mounted to the link 70 viarespective axles which define respective axes of rotation of the supportwheels 28 ₁, 28 ₂. In this embodiment, the pivot axis of the link 70lies closer to the axis of rotation of the support wheel 28 ₁ than thatof the support wheel 28 ₂ and above the axes of rotation of the supportwheels 28 ₁, 28 ₂. The pivot axis of the link 70 and the axes ofrotation of the support wheels 28 ₁, 28 ₂ may be positioned differentlyin relation to one another in other embodiments (e.g., the pivot axis ofthe link 70 may lie equidistant between the axes of rotation of thesupport wheels 28 ₁, 28 ₂). The bogie 50 ₂ is configured similarly tothe bogie 50 ₁ and will thus not be further discussed.

In this embodiment, each support wheel 28 _(i) facilitates installationof the endless track 22. More particularly, in this embodiment, withadditional reference to FIGS. 35 and 36, the support wheel 28 comprisesa first support wheel member 35 ₁ and a second support wheel member 35 ₂which each have a circumference of the support wheel 28 _(i), arerotatable about the axle of support wheel 28 _(i), and are installablein and removable from the track assembly 16 _(i) separately from oneanother. The support wheel member 35 ₁, which is farthest from acenterline of the vehicle 1, can be viewed as an “outboard” supportwheel member while the support wheel member 35 ₂, which is nearest tothe centerline of the vehicle 10, can be viewed as an “inboard” supportwheel member. The endless track 22 can be installed while the inboardsupport wheel member 35 ₂ is in place but before placement of theoutboard support wheel member 31 ₁, which is put in place afterinstallation of the endless track 22. This makes it easier to install orreplace the endless track 22.

More particularly, in this embodiment, the outboard and inboard supportwheel members 35 ₁, 35 ₂ are secured to a hub 36 by fasteners 48 ₁-48_(F) (e.g., bolts and nuts). The hub 36 includes an opening 52 thatreceives the axle of the support wheel 28 _(i). In this embodiment,bearings (e.g., tapered bearings) are positioned in the opening 52 ofthe hub 36 and receive the axle of the support wheel 28 _(i). A cap 54covers an end of the axle of the support wheel 28 _(i). The axle of thesupport wheel 28 _(i) extends and is fixed to the link 70 of the bogie50 _(i). In this case, a fastener 56 (e.g., a bolt) extendstransversally to the axle of the support wheel 28 _(i) and through thelink 70 to fix the axle to the link 70. The outboard and inboard supportwheel members 35 ₁, 35 ₂ may be mounted in any other suitable way inother embodiments.

As further discussed later, in this embodiment, the outboard and inboardsupport wheel members 35 ₁, 35 ₂ define in between them a guiding space38 for receiving a wheel guide of the endless track 22 to guide theendless track 22 as it moves around the wheels 24, 23, 28 ₁-28 ₄.

In this embodiment, each support wheel member 35 _(i) comprises a rimportion 57, a hub portion 58, and a radially-extending portion 61therebetween. The rim portion 57 is in rolling contact with the bottomrun 42 of the endless track 22. The hub portion 58 is a central portionof the support wheel member 35 _(i) which receives the axle of thesupport wheel 28 _(i). In this example, the hub portion 58 engages thehub 36 and is secured thereto by the fasteners 48 ₁-48 _(F). Theradially-extending portion 61 extends from the rim portion 57 to the hubportion 58. In this example, the radially-extending portion 61 comprisesa plurality of spokes 63 ₁-63 ₈ and a plurality of interspoke openings67 ₁-67 ₈ between adjacent ones of the spokes 63 ₁-63 ₈.

More particularly, in this embodiment, the rim portion 57, the hubportion 58, and the radially-extending portion 61 are configured suchthat the support wheel member 35 _(i) is a concave support wheel memberdefining a concavity 69. Each of the spokes 63 ₁-63 ₈ tapers radiallytowards the hub portion 58. The support wheel member 35 _(i) may haveany other suitable shape in other embodiments.

In this example of implementation, the support wheel member 35 _(i) is ametallic support wheel member (e.g., a steel support wheel member) thathas been cast into shape. The support wheel member 35 _(i) may be madeof any other suitable material and/or using any other suitablemanufacturing process in other examples of implementation.

The support wheels 28 ₁-28 ₄ may be configured in various other ways inother embodiments. For example, in other embodiments, a support wheelmember 35 _(i) of a support wheel 28 _(i) may comprise a rubber or otherelastomeric covering on its rim portion 57 to be in rolling contact withthe bottom run 42 of the endless track 22. As another example, in otherembodiments, a support wheel 28 _(i) may be a unitary support wheelwhich does not comprise separate outboard and inboard support wheelmembers as discussed above. For instance, in some embodiments, as shownin FIGS. 39 and 40, a support wheel 28 _(i) may be a unitary supportwheel which comprises a metallic wheel body 93 on which is mounted atire 91 that is in rolling contact with the bottom run 42 of the endlesstrack 22.

In this embodiment, as shown in FIGS. 3, 9, 15 and 20, the idler wheel23 overlaps the rearmost support wheel 28 ₄ in the longitudinaldirection of the tracked utility vehicle 10. This may be beneficial forstability of the vehicle 10 when the work equipment 41 applies asignificant load in a rear end region of the chassis 12 (e.g., when adrill, dump bucket or other piece of equipment is raised in the rear endregion of the chassis 12). The longitudinal overlap between the idlerwheel 23 and the support wheel 28 ₄ allows the longitudinal distancebetween the pivot axis defined by the pivot 71 of the bogie 50 ₂ and therear end region of the chassis 12 to be less than if there was nolongitudinal overlap between the idler wheel 23 and the support wheel 28₄. This smaller longitudinal distance results in a smaller moment armand, consequently, a smaller moment associated with the load applied bythe work equipment 41 in the rear end region of the chassis 12.

More particularly, in this embodiment, the idler wheel 23 longitudinallyoverlaps the support wheel 28 ₄ by being located in the guiding space 38between the inboard and outboard wheel members 35 ₁, 35 ₂ of the supportwheel 28 ₄. The longitudinal overlap between the idler wheel 23 and thesupport wheel 28 ₄ may be achieved in various ways in other embodiments.For example, in embodiments in which the support wheel 28 ₄ is a unitarysupport wheel which does not comprise separate outboard and inboardsupport wheel members (e.g., as shown in FIGS. 39 and 40), the idlerwheel 23 may comprise an inboard idler wheel member and an outboardidler wheel member that define a space therebetween in which the supportwheel 28 ₄ may be located such that the idler wheel 23 and the supportwheel 28 ₄ longitudinally overlap.

The endless track 22 engages the ground to provide traction to thetracked utility vehicle 10. More particularly, as the drive wheel 24 isrotated by power derived from the power plant 14, the drive wheel 24imparts motion to the endless track 22 for traction of the vehicle 10 onthe ground. The endless track 22 has an inner side 32 facing the wheels24, 23, 28 ₁-28 ₄ and a ground-engaging outer side 33, opposite theinner side 32, for engaging the ground.

In this embodiment, as shown in FIGS. 29 and 30, the endless track 22comprises an elastomeric body 37 underlying its inner side 32 and itsground-engaging outer side 33. The body 37 is elastomeric in that itcomprises elastomeric material which allows the track 22 to elasticallychange in shape as it is in motion around the wheels 24, 23, 28 ₁-28 ₄.The elastomeric material of the body 37 can be any polymeric materialwith suitable elasticity. In this embodiment, the elastomeric materialincludes rubber. Various rubber compounds may be used and, in somecases, different rubber compounds may be present in different areas ofthe track 22. In other embodiments, the elastomeric material may includeanother elastomer in addition to or instead of rubber (e.g.,polyurethane elastomer).

A plurality of cores 21 ₁-21 _(C) are embedded in the elastomericmaterial of the body 37 of the endless track 22, spaced apart along thelongitudinal direction of the track 22, and extending transversally tothe longitudinal direction of the track 22 to impart transverse rigidityto the track 22. The cores 21 ₁-21 _(C) are made of rigid material. Forinstance, in this embodiment, the cores 21 ₁-21 _(C) are metallic (e.g.,steel) cores. This type of track can thus sometimes be referred to as a“metal-embedded rubber track” (MERT).

The cores 21 ₁-21 _(C) interact with the wheels 24, 23, 28 ₁-28 ₄ toimpart and/or guide motion of the endless track 22. For example, in thisembodiment, the track 22 has a plurality of drive openings 19 ₁-19 _(O)for receiving teeth of the drive wheel 24 such that the drive wheel 24can engage parts of the track 22 where are located individual ones ofthe cores 21 ₁-21 _(C) in order to apply motive force to the track 22.The cores 21 ₁-21 _(C) also guide motion of the track 22 as it is drivenby the drive wheel 24. More particularly, each core 21 _(i) comprises apair of wings 29 ₁, 29 ₂ and a wheel guide 25 between the wings 29 ₁, 29₂. The wheel guide 25 comprises at least one, in this case, two guideprojections 36 ₁, 36 ₂ projecting on the inner side 32 of the endlesstrack 22. In this embodiment, when its teeth enter the drive openings 19₁-19 _(O) of the track 22, the drive wheel 24 engages the wheel guide 25of the core 21 _(i) between the guide projections 36 ₁, 36 ₂ to drivethe track 22, while the guide projections 36 ₁, 36 ₂ pass in the guidingspace 38 defined by each of the support wheels 28 ₁-28 ₄ in order toguide the track 22 relative to the support wheels 28 ₁-28 ₄.

One or more reinforcements may be embedded in the elastomeric materialof the body 37 of the endless track 22. For instance, a reinforcementmay be a layer of reinforcing cables 43 ₁-43 _(R) that are adjacent toone another and that extend in the longitudinal direction of the track22 to enhance strength in tension of the track 22 along its longitudinaldirection. In some cases, a reinforcing cable 43 _(i) may be a cord orwire rope including a plurality of strands or wires. In other cases, areinforcing cable 43 _(i) may be another type of cable and may be madeof any material suitably flexible longitudinally (e.g., fibers or wiresof metal, plastic or composite material). Various other types ofreinforcements may be provided in other embodiments.

The ground-engaging outer side 33 of the endless track 22 comprises atread pattern to enhance traction on the ground. The tread patterncomprises a plurality of traction projections 49 ₁-49 _(T), which can bereferred to as “traction lugs”, spaced apart along the longitudinaldirection of the track 22 and engaging the ground to enhance traction.

The inner side 32 of the endless track 22 comprises the guideprojections 36 ₁, 36 ₂ of each of the cores 21 ₁-21 _(C). In addition,the inner side 32 of the track 22 comprises rolling surfaces 39 ₁, 39 ₂on which the support wheels 28 ₁-28 ₄ roll to apply the track 22 ontothe ground.

The endless track 22 may be configured in various other ways in otherembodiments.

For example, in some embodiments, as shown in FIGS. 31 and 32, theendless track 22 may comprise a pair of belts 30 ₁, 30 ₂ spaced apart toaccommodate the wheels 24, 23, 28 ₁-28 ₄ and a series of cross-links 31₁-31 _(N) distributed longitudinally along the track 22 and extendingtransversally to interconnect the belts 30 ₁, 30 ₂.

Each belt 30 _(i) is elastomeric in that it comprises rubber and/orother elastomeric material. The belt 30 _(i) may comprise one or morereinforcements such as a layer of cables embedded in its rubber and/orother elastomeric material. In this case, the belt 30 _(i) is made up ofa series of belt sections connected to one another. In other cases, thebelt 30 _(i) may be a one-piece belt.

The cross-links 31 ₁-31 _(N) interconnect the belts 30 ₁, 30 ₂ andinteract with the wheels 24, 23, 28 ₁-28 ₄ as the endless track 22 movesaround these wheels. For example, in this embodiment, as the drive wheel24 rotates, individual ones of the cross-links 31 ₁-31 _(N) engagerecesses between the teeth of the drive wheel 24, thereby causing thetrack 22 to be driven. Also, the cross-links 31 ₁-31 _(N) help to guidemotion of the track 22 by contacting the support wheels 28 ₁-28 ₄. Moreparticularly, each cross-link 31 _(i) comprises a wheel guide 44including a pair of guide projections 45 ₁, 45 ₂ projecting on the innerside 32 of the endless track 22. In this embodiment, when its teethenter gaps between the cross-links 31 ₁-31 _(N), the drive wheel 24engages the wheel guide 44 of the cross-links 28 ₁-28 ₄ between theguide projections 45 ₁, 45 ₂ to drive the track 22, while the supportwheels 28 ₁-28 ₄ pass between the guide projections 45 ₁, 45 ₂ in orderto guide the track 22 relative to the support wheels 28 ₁-28 ₄. In suchembodiments, each of the support wheels 28 ₁-28 ₄ may be a unitarysupport wheel as shown in FIGS. 39 and 40.

Each cross-link 31 _(i) comprises an elongated member 73 extendingtransversally to the longitudinal direction of the endless track 22 tointerconnect the belts 30 ₁, 30 ₂. The elongated member 73 is made ofrigid material, in this case metallic material (e.g., steel). Theelongated member 73 is secured to the belts 30 ₁, 30 ₂ by fastenerswhich extend through the elongated member 73, the belts 30 ₁, 30 ₂, andbacking plates 75 ₁, 75 ₂ disposed on the inner side 32 of the track 22.In this embodiment, the cross-link 31 ₁ comprises a polymeric sole 77mounted to the elongated member 73. The polymeric sole 77 can be usedwhen the vehicle 10 is to travel on a hard surface (e.g., a pavedsurface) in order to minimize an impact of the cross-link 31 _(i) onthat surface. In other embodiments, the cross-link 31 _(i) may notinclude any polymeric sole.

As another example, in some embodiments, the endless track 22 maycomprises an endless elastomeric body underlying its inner side 32 andits ground-engaging outer side 33, similar to the elastomeric body 37discussed above in respect of FIGS. 29 and 30, but without coresembedded in the elastomeric body (e.g., an “all-rubber” track).

In this embodiment, the track assembly 16 _(i) comprises a plurality ofwheel mounting structures for mounting the wheels 24, 23, 28 ₁-28 ₄ tothe chassis 12, including a drive wheel mounting structure 88 ₁, a pairof support wheel mounting structures 88 ₂, 88 ₃, and an idler wheelmounting structure 88 ₄, which are secured to the chassis 12 and spacedapart in the longitudinal direction of the tracked utility vehicle 10.Each of the wheel mounting structures 88 ₁-88 ₄ supports at least one ofthe wheels 24, 23, 28 ₁-28 ₄. Specifically, in this case, the drivewheel mounting structure 88 ₁ supports the drive wheel 24, the supportwheel mounting structures 88 ₂, 88 ₃ support the bogies 50 ₁, 50 ₂carrying the support wheels 28 ₂-28 ₄, and the idler wheel mountingstructure 88 ₄ supports the idler wheel 23.

The track assembly 16 _(i) comprises a track tensioner 85 formaintaining tension of the endless track 22. In this embodiment, thetrack tensioner 85 is connected between the support wheel mountingstructure 88 ₃ and axle of the idler wheel 23 to urge the idler wheel 23in a direction to maintain the tension of the endless track 22. Also, inthis embodiment, the track tensioner 68 is a fluidic tensioning system,e.g., a hydraulic or pneumatic tensioning system, which comprises apiston-cylinder tensioning actuator 79 connected to a fluid reservoir.In this example of implementation, the tensioning actuator 79 is ahydraulic piston-cylinder actuator.

More particularly, in this embodiment, with additional reference toFIGS. 37 and 38, the tensioning actuator 79 is connected to the supportwheel mounting structure 88 ₃ and to an idler wheel support arm 83 whichis pivotable about an axle 89 that is fixed to the idler wheel mountingstructure 88 ₄. The axle of the idler wheel 23 is fixed to the idlerwheel support arm 83. The tensioning actuator 79 can apply the tensionin the track 22 by extending or retracting to turn the idler wheelsupport arm 83 about the axle 89 and thus move the idler wheel 23further or closer to the drive wheel 24.

In this embodiment, the track tensioner 85 becomes active when thetracked utility vehicle 10 is started. That is, the track tensioner 85applies a force to generate the tension in the endless track 22 when theprime mover 17 of the vehicle 10 is started.

With additional reference to FIG. 48, in this embodiment, the tracktensioner 85 is hydraulically connected to the hydraulic drive system 21of the vehicle 10 such that the tension in the endless track 22 isgenerated by the hydraulic fluid of the hydraulic drive system 21. Thetensioning actuator 79 is in hydraulic communication with the hydraulicdrive system 21 such that, when the prime mover 17 is started and startsto power the hydraulic drive system 21, the hydraulic fluid of thehydraulic drive system 21 acts on the tensioning actuator 79, whichapplies a force to generate the tension in the endless track 22.

More particularly, as shown in FIG. 49, in this embodiment, thehydraulic drive system 21 comprises a charge pump 27 hydraulicallyconnected to the tensioning actuator 79 via a track tensioner hydrauliccircuit 13.

The charge pump 27 is operative to maintain a minimum pressure in thehydraulic drive system 21 when the vehicle 10 is turned on. For example,in some embodiments, the minimum pressure may be at least 300 psi, insome cases at least 325 psi, and in some cases at least 350 psi. Forinstance, in this embodiment, the minimum pressure is about 375 psi. Theminimum pressure in the hydraulic drive system 21 may have any othersuitable value in other embodiments. In this example of implementation,the charge pump 27 is a fixed displacement pump. For instance, thecharge pump 27 may be a gear pump, a gerotor pump or any other suitabletype of pump.

The hydraulic fluid from the charge pump 27 causes the tensioningactuator 79 to apply a force to generate the tension in the endlesstrack 22. This force corresponds to the pressure of the hydraulic fluidin the tensioning actuator 79 multiplied by a cross-sectional area ofthe piston-cylinder arrangement of the tensioning actuator 79. Forexample, in some embodiments, the force may be at least 5000 pounds, insome cases at least 6000 pounds, in some cases at least 7000 pounds, andin some cases even more (e.g., up to 10000 pounds). For instance, inthis embodiment, the piston-cylinder arrangement of the tensioningactuator 79 may have an internal diameter of 5 inches such that itsinternal cross-sectional area is approximately 19.6 square inches and,at the minimum pressure of 375 psi, the force applied by the tensioningactuator 79 is about 7363 pounds. The force may have any other value inother embodiments.

The track tensioner hydraulic circuit 13 regulates flow of hydraulicfluid between the charge pump 27 and the tensioning actuator 79. Forexample, in this embodiment, the track tensioner hydraulic circuit 13limits a maximum pressure that is applicable to the tensioning actuator79. This may be useful, for instance, to prevent situations (e.g., harddebris becoming stuck between the drive wheel 24 and the endless track22) where the tension in the endless track 22 would become too high.More particularly, with additional reference to FIG. 50, in thisembodiment, the track tensioner hydraulic circuit 13 comprises apressure limiter 98 to limit the maximum pressure that is applicable tothe tensioning actuator 79. In this example of implementation, thepressure limiter 79 comprises a valve 97 (e.g., a relief valve) whichopens at a preset pressure which corresponds to the maximum pressurethat is not to be exceeded in the tensioning actuator 97. For example,in some embodiments, the preset pressure at which the valve 97 opens,which corresponds to the maximum pressure allowable in the tensioningactuator 79, may be at least 1000 psi, in some cases at least 1200 psi,in some cases at least 1400 psi, and in some cases even more. Forinstance, in this embodiment, the preset pressure at which the valve 97opens is 1400 psi such that the pressure in the tensioning actuator 79can vary between 375 psi and 1400 psi. The maximum pressure may have anyother suitable value in other embodiments

In this embodiment, the track tensioner hydraulic circuit 13 is arrangedsuch that, if the vehicle 10 is momentarily turned off (e.g., for a fewminutes) the tension in the endless track 22 is maintained by thetensioning cylinder 79. For example, in this embodiment, the tracktensioner hydraulic circuit 13 comprises a check valve 123 arranged forthat purpose.

Although in this embodiment the track tensioner 85 is hydraulicallyconnected to the hydraulic drive system 21 of the vehicle 10 via thecharge pump 27 such that the tension in the endless track 22 isgenerated when the prime mover 17 is started and starts to power thehydraulic drive system 21, the track tensioner 85 may be connected inother ways such that it would become active when the vehicle 10 isstarted (e.g., there may be a dedicated pump for the track tensioner85).

The track assembly 16 _(i) may be configured in various other ways inother embodiments. For example, although in this embodiment it comprisesfour (4) support wheels 28 ₁-28 ₄, the track assembly 16 _(i) maycomprise more than four support wheels (e.g., five (5) support wheels)in other embodiments. As another example, while in this embodiment thedrive wheel 24 is located in a front region of the chassis 12 and theidler wheel 23 is located in a rear region of the chassis 12, this maybe reversed in other embodiments such that the drive wheel 24 is locatedin a rear region of the chassis 12 and the idler wheel 23 of the trackassembly 16 _(i) is located in a front region of the chassis 12. As yetanother example, while in this embodiment the idler wheel 23 is not in adriven relationship with the power plant 14, in other embodiments, theidler wheel 23 may be replaced by another drive wheel that is in adriven relationship with the power plant 14.

c) Operator Cabin

The operator cabin 20 is where an operator sits and controls the trackedutility vehicle 10. In this embodiment, the operator cabin 20 comprisesa front side 112, a rear side 114, a pair of lateral sides 116 ₁, 116 ₂,a roof 118, and a floor 120. The lateral side 116 ₁ of the operatorcabin 20 defines an access opening 122 that can be closed by a door 124and that allows the operator to enter or exit the operator cabin 20. Aplurality of windows 126 ₁-126 _(W) are provided to allow the operatorto see outside of the vehicle 10.

With additional reference to FIG. 41, the operator cabin 20 comprises aseating area 132 and a user interface 130. As further discussed lateron, in this embodiment, the operator cabin 20 is configurable in aplurality of cabin configurations in which the seating area 132 and theuser interface 130 are configured differently.

The user interface 130 enables the operator to interact with the trackedutility vehicle 10. For example, the user interface 130 comprisescontrols allowing the operator to move the tracked utility vehicle 10 onthe ground. In some cases, the user interface 130 may also includecontrols for controlling the work equipment 41 carried by the vehicle10. The user interface 130 comprises an input portion to allow theoperator to input commands for execution by the vehicle 10 and an outputportion to convey information to the operator.

In this embodiment, the input portion of the user interface 130comprises an accelerator 133, a steering device 134, a transmissionstate selector 135, a starter switch 137, and a control lever 138. Moreparticularly:

-   -   The accelerator 133 allows the operator to control a speed of        the vehicle 10 on the ground. In this example, the accelerator        133 comprises a speed pedal operated by a foot of the operator.        The accelerator 133 may be implemented in other ways in other        examples (e.g., a hand-operated accelerator).    -   The steering device 134 allows the operator to steer the vehicle        10 on the ground. In this example, the steering device 134        comprises a steering wheel that is rotatable relative to a        steering column 144 about a steering axis. In addition to the        steering wheel 134, in this example of implementation, the        steering column 144 supports the transmission state selector        135, the starter switch 137, and the control lever 138. The        steering device 134 may be implemented in other ways in other        embodiments (e.g., a joystick).    -   The transmission state selector 135 allows the operator to        control a state of power transmission to the track assemblies 16        ₁, 16 ₂. For instance, in this example, the transmission state        selector 135 comprises a proportional front-neutral-reverse        selector to control whether power is transmitted to the track        assemblies 16 ₁, 16 ₂ to move in a forward or reverse direction        or not transmitted to the track assemblies 16 ₁, 16 ₂. The        transmission state selector 135 may be implemented in other ways        in other embodiments.

The starter switch 137 allows the operator to start the prime mover 17of the vehicle 10. For instance, in this example, the starter switch 137comprises a key-receiving unit to receive a key to start the prime mover17 of the vehicle 10. The starter switch 137 may be implemented in otherways in other embodiments (e.g., a start button, a code entry device, abiometric authentication device, etc.).

-   -   The control lever 138 allows the operator to control various        devices of the vehicle 10. For instance, in this example, the        control lever 138 includes a wiper control which allows the        operator to control a wiper 140 of the front window 126 ₁ of the        operator cabin 20, a washer fluid control which allows the        operator to control outflow of washer fluid from a washer fluid        nozzle onto the front window 126 ₁, and a turning indicator 141        control which allows the operator to control a turning indicator        of the vehicle 10. The control lever 138 may include any other        suitable control in other examples.

The input portion of the user interface 130 may comprise any other inputdevice (e.g., a set of buttons, a joystick, a trackball, etc.) in otherembodiments.

In this embodiment, the output portion of the user interface 130comprises a display 140 to visually convey information to the operator.The display 140 may be any suitable type of electronic display (e.g., aliquid-crystal display (LCD), etc). Various information can be conveyedto the operator on the display 140. For example, in some embodiments,the display 140 may implement an instrument panel that provides: aspeedometer indicator which conveys information indicative of the speedat which the vehicle 10 is moving as measured by a speedometer of thevehicle 10; a tachometer indicator which conveys information indicativeof the speed at which the prime mover 17 is running as measured by atachometer of the vehicle 10; an odometer indicator which conveysinformation indicative of a distance traveled by the vehicle 10 asmeasured by an odometer of the vehicle 10; a fuel gauge indicator whichconveys information indicative of a quantity of fuel remaining in thevehicle 10; and/or any other indicator conveying information to theuser. Each of the speedometer indicator, the tachometer indicator, theodometer indicator, and/or other indicators may comprise a digitalnumerical reading, a digital dial, a digital bar graph, a digitalsymbol, and/or any other element displayable on the display 140 toconvey information to the operator.

The output portion of the user interface 130 may comprise any otheroutput device (e.g., one or more mechanical dials (e.g., a speedometerdial, a fuel gauge dial, etc.) or other mechanical indicators (e.g., amechanical odometer); one or more light indicators (e.g., low fuel lightindicator, etc.); a speaker; etc.) in other embodiments.

The user interface 130 is connected to other components of the trackedutility vehicle 10 to cause execution of commands provided by theoperator and to present information to the operator. More particularly,in this embodiment, there are a plurality of connections 142 ₁-142 _(C)between the user interface 130 and other components of the vehicle 10.These connections 142 ₁-142 _(C) may comprise one or more mechanicallinks, wires, cables, wireless links, and/or other connecting elementsdepending on how the user interface 130 is connected to other componentsof the vehicle 10 (e.g., via mechanical control systems and/or viaelectromechanical systems (e.g., “drive-by-wire” systems)). For example,with additional reference to FIG. 45, in this embodiment:

-   -   The connection 142 ₁ is between the speed pedal 133 and the        prime mover 17. For instance, in this embodiment, the connection        142 ₁ may comprise a wire connected to a pedal position sensor        (e.g., comprising a potentiometer) for sensing a position of the        speed pedal 133 and transmitting a signal indicative of this        position to a powertrain controller 147 controlling the prime        mover 17 (e.g., an engine control unit (ECU)). In other        embodiments, the connection 142 ₁ may comprise a mechanical link        between the speed pedal 133 and a throttle for the prime mover        17.    -   The connection 142 ₂ is between the steering wheel 134 and a        steering controller 143 which controls a steering direction of        the vehicle 10 by controlling the hydraulic motors of the        hydraulic drive system 21 to cause the endless track 22 of one        of the track assemblies 16 ₁, 16 ₂ to move faster than the        endless track 22 of the other one of the track assemblies 16 ₁,        16 ₂ when the vehicle 10 turns. For instance, in this        embodiment, the connection 142 ₂ comprises a steering device        angle sensor for sensing an angle in which the steering wheel        134 is positioned and transmitting a signal indicative of this        angle to the steering controller 143.    -   The connection 142 ₃ is between the proportional        front-neutral-reverse selector 135 and the powertrain controller        147. For instance, in this embodiment, the connection 142 ₃ may        comprise a wire transmitting a signal indicative of the state of        the selector 135 to the powertrain controller 147.    -   The connection 142 ₄ is between the starter switch 137 and the        prime mover 17. For instance, in this embodiment, the connection        142 ₄ may comprise a wire between the starter switch 137 and the        powertrain controller 147.    -   The connections 142 ₅-142 _(C) are between the control lever 138        and the wiper 140, the washer fluid nozzle, the turning        indicator 141 and/or any other device of the vehicle 10 which        can be controlled via inputs at the control lever 138. For        instance, in this embodiment, the connections 142 ₆-142 _(N) may        comprise wires between the control lever 138 and an outside        functionality controller 149 of the vehicle 10 which sends        signals to these devices of the vehicle 10 to control these        devices. In other embodiments, the connections 142 ₆-142 _(N)        may comprise wires directly connected to these devices.

Controllers of the tracked utility vehicle 10, such as the powertraincontroller 147, the steering controller 143 and the outsidefunctionality controller 149, with which the user interface 130 mayinteract may be implemented in various manners. A controller comprisessuitable hardware and/or software (e.g., firmware) implementing: aninterface for receiving and transmitting signals to other components ofthe vehicle 10 to which it is connected; a processing portion comprisingone or more processors for performing processing operations, where aprocessor may be a general-purpose processor executing program codestored in the controller or a specific-purpose processor comprising oneor more preprogrammed hardware or firmware elements (e.g.,application-specific integrated circuits (ASICs), electrically erasableprogrammable read-only memories (EEPROMs), etc.); and a memory portioncomprising one or more memories for storing program code executed by theprocessing portion and/or data used during operation of the processingportion, where a memory may be a semiconductor memory (e.g., read-onlymemory (ROM) and/or random-access memory (RAM)), a magnetic storagemedium, an optical storage medium, and/or any other suitable type ofmemory. In some embodiments, two (2) or more (e.g., all) controllers ofthe vehicle 10 may be physically distinct from one another and may beconnected to one another via a bus (e.g., a controller-area network(CAN) bus or other suitable bus). In other embodiments, two (2) or more(e.g., all) controllers of the vehicle 10 may be functional entities ofa single physical control unit (e.g., a vehicle controller).

The seating area 132 comprises a seat 150 for the operator of thetracked utility vehicle 10. The seat 150, which will be referred to asan “operator seat”, is positioned relative to the user interface 130 toallow the operator to easily interact with the user interface 130.

As mentioned previously, in this embodiment, the operator cabin 20 isconfigurable into a plurality of cabin configurations in which theseating area 132 and the user interface 130 are configured differently.More particularly, in this embodiment, the plurality of cabinconfigurations in which the operator cabin can be configured includes afirst cabin configuration, which is shown in FIGS. 41 and 42 and will bereferred to as a “one-person cabin configuration”, and a second cabinconfiguration, which will be referred to as a “two-person cabinconfiguration” and is shown in FIGS. 43 and 44.

As shown in FIG. 41, the operator cabin 20 can be configured in theone-person cabin configuration when only the operator is to sit therein.More particularly, in this embodiment, the operator seat 150 is a soleseat of the seating area 132 and is located in an operator seat position176 which, in this example, is generally in a center of a width of aninterior of the operator cabin 20. Various devices of the user interface130, including the steering wheel 134 and its steering column 144, thespeed pedal 133, the front-neutral reverse selector 135, the starterswitch 137, and the control lever 138, are also located in respectiveuser device positions which, in this example, are generally in thecenter of the width of the interior of the operator cabin 20.

As shown in FIG. 43, the operator cabin 20 can be configured in thetwo-person cabin configuration when the operator and a second person areto sit therein. More particularly, in this embodiment, the operatorcabin 20 is sized such that it allows the second person, who will bereferred to as a “passenger”, to sit in the seating area 132 with theoperator. To that end, the seating area 132 allows a second seat 152 tobe provided for the passenger. The seat 152, which will be referred toas a “passenger seat”, is located adjacent to the operator seat 150 suchthat the operator and the passenger sit side-by-side.

The seating area 132 and the user interface 130 in the one-person cabinconfiguration are configured differently than in the two-person cabinconfiguration. More particularly, in this embodiment, the operator seat150 and devices of the user interface 130 in the two-person cabinconfiguration are located in respective positions that are differentfrom those in which they are located in the one-person cabinconfiguration.

An operator seat position 177 of the operator seat 150 in the two-personcabin configuration is different from the operator seat position 176 ofthe operator seat 150 in the one-person cabin configuration. In thisexample, the operator seat position 177 of the operator seat 150 in thetwo-person cabin configuration is displaced in the widthwise directionof the vehicle 10 such that the operator seat 150 is closer to the rightside 116 ₂ of the operator cabin 20 in the two-person cabinconfiguration than in the one-person cabin configuration. The passengerseat 152 is located at a passenger seat position 178 that is between theleft side 116 ₁ of the operator cabin 20 than the operator seat 150.

The seating area 132 thus defines a plurality of seat positions alongthe widthwise direction of the vehicle 10, including the operator seatposition 176 in the one-person cabin configuration, the operator seatposition 177 in the two-person cabin configuration, and the passengerseat position 178 in the two-person cabin configuration. In thisembodiment, the seating area 132 comprises a seat support 151 formounting the operator seat 150 in its operator seat positions 176, 177in the one-person cabin configuration and the two-person cabinconfiguration and for mounting the passenger seat 152 in its passengerseat position 178 adjacent to the operator seat 150 in the two-personcabin configuration. More particularly, in this embodiment, the seatsupport 151 comprises mounting holes 154 ₁-154 _(H) in the floor 120 ofthe operator cabin 20 to receive fasteners (e.g., bolts) for mountingthe operator seat 150 or the passenger seat 152 to the seat support 151(e.g., four bolts in four corners of the seat's base). In otherembodiments, the seat support 151 may comprise mounting projections,mounting brackets, and/or other mounting structures to mount theoperator seat 150 or the passenger seat 152 to the seat support 151.Also, in this embodiment, a seatbelt for the operator seat 150 remainsthe same in the one-person cabin configuration and the two-person cabinconfiguration, while an additional seatbelt is installed on thepassenger's side in the two-person cabin configuration.

User device positions of devices of the user interface 130, includingthe steering wheel 134 and its steering column 144, the speed pedal 133,the front-neutral reverse selector 135, the starter switch 137, and thecontrol lever 138, in the two-person cabin configuration are differentfrom the user device positions of these devices in the one-person cabinconfiguration. In this example, the positions of the steering wheel 134and its steering column 144, the speed pedal 133, the front-neutralreverse selector 135, the starter switch 137, and the control lever 138in the two-person cabin configuration are displaced in the widthwisedirection of the vehicle 10 such that these devices are closer to rightside 116 ₂ of the operator cabin 20 in the two-person cabinconfiguration than in the one-person cabin configuration.

The operator cabin 20 comprises a user interface support 160 formounting devices of the user interface 130, including the steering wheel134 and its steering column 144, the speed pedal 133, the front-neutralreverse selector 135, the starter switch 137, and the control lever 138,such that these devices are movable between the one-person cabinconfiguration and the two-person cabin configuration. More particularly,in this embodiment, the speed pedal 133 and the steering column 144,which supports the steering wheel 134, the front-neutral reverseselector 135, the starter switch 137, and the control lever 138, aremounted to the user interface support 160 such that they are movable inthe widthwise direction of the vehicle 10 to change the operator cabin20 between the one-person cabin configuration and the two-person cabinconfiguration.

The user interface support 160 defines a plurality of steering devicepositions for the steering wheel 134 and its steering column 144 alongthe widthwise direction of the vehicle 10, including a central steeringdevice position 161 in the one-person cabin configuration and a sidesteering device position 162 in the two-person cabin configuration. Theuser interface support 160 also defines a plurality of acceleratorpositions for the speed pedal 133 along the widthwise direction of thevehicle 10, including a central accelerator position 163 in theone-person cabin configuration and a side accelerator position 164 inthe two-person cabin configuration. In this embodiment, with additionalreference to FIG. 46, the user interface support 160 comprises mountingholes 167 ₁-167 ₂₀ for receiving fasteners (e.g., bolts) to fasten thesteering column 144 and the speed pedal 133 to the user interfacesupport 160 in respective ones of their central and side steering devicepositions 161, 162 and central and side accelerator positions 163, 164in the one-person cabin configuration and the two-person cabinconfiguration. In other embodiments, the user interface support 160 maycomprise mounting projections, mounting brackets, and/or other mountingstructures to mount the steering column 144 and the speed pedal 133 tothe user interface support 160.

More particularly, in this embodiment, the user interface support 160comprises a fixed support structure 165 and a movable support structure166 that can be moved relative to the fixed support structure 165. Thesupport structures 165, 166 define respective ones of the mounting holes167 ₁-167 ₂₀ which can be aligned with one another to receive fasteners.

In this example of implementation, the fixed support structure 165comprises a fixed plate 169 which extends obliquely to a horizontalsurface of the floor 120 and another fixed plate 170 which also extendsobliquely to the horizontal surface of the floor 120 but at a lesserangle than the fixed plate 169. The fixed plates 169, 170 define themounting holes 167 ₁-167 ₁₅. The movable support structure 166 comprisesa movable plate 171 and another movable plate 173 which respectivelyoverlap the fixed plates 169, 170 and define the mounting holes 167₁₆-167 ₂₀. The movable plate 171 also comprises a steering columnopening 172 through which wires from the steering column 144 extend andmounting holes 175 ₁-175 ₄ to receive fasteners fastening the steeringcolumn 144 to the user interface support 160.

The steering column 144 can be moved from its central steering deviceposition 161 in the one-person cabin configuration to its side steeringdevice position 162 in the two-person cabin configuration by: releasingfasteners (e.g., unscrewing bolts) received in the mounting holes 167 ₁,167 ₂, 167 ₄, 167 ₆, 167 ₇ of the fixed plates 169, 170 and the mountingholes 167 ₁₆-167 ₂₀ of the movable plates 171, 173; moving the movablesupport structure 166 relative to the fixed support structure 165 in thewidthwise direction of the vehicle 10 toward the right such that themounting holes 167 ₁₆-167 ₂₀ of the movable support structure 166 alignwith the mounting holes 167 ₃, 167 ₄, 167 ₅, 167 ₁₁, 167 ₁₂ of the fixedsupport structure 165; and using fasteners in these aligned ones of themounting holes 167 ₁-167 ₂₀ to re-fasten the movable support structure166 to the fixed support structure 165. Wires from the steering column144 can be disconnected, moved, and reconnected to move the steeringcolumn 144 between its central steering device position and sidesteering device position.

The speed pedal 133 can be moved from its central accelerator position163 in the one-person cabin configuration to its side acceleratorposition 164 in the two-person cabin configuration by: releasingfasteners (e.g., unscrewing bolts) received in the mounting holes 167₈-167 ₁₀ of the fixed plate 170 and holes of the speed pedal 133; movingthe speed pedal 133 relative to the fixed support structure 165 in thewidthwise direction of the vehicle 10 toward the right such that theholes of the speed pedal 133 align with the mounting holes 167 ₁₃-167 ₁₅of the fixed support structure 165; and using fasteners in these alignedholes to re-fasten the speed pedal 133 to the fixed support structure165.

The steering column 144 and the speed pedal 133 can be moved from theirside steering device position 162 and side accelerator position 164 inthe two-person cabin configuration to their central steering deviceposition 161 and central accelerator position 163 in the one-personcabin configuration using a procedure that is reverse to that describedabove.

The seat support 151 and/or the user interface support 160 may beconstructed in various other ways in other embodiments to provide thedifferent seat positions 176, 177, 178, steering device positions 161,162, and/or accelerator positions 163, 164. For example, in otherembodiments, the seat support 151 and/or the user interface support 160may provide the different seat positions 176, 177, 178, steering devicepositions 161, 162, and/or accelerator positions 163, 164 by allowingthe operator seat 150, the steering column 144, and/or the speed pedal133 to be moved between such different positions without having tountighten bolts or other fasteners (e.g., a rail mechanism which allowsthe steering column 144 and/or the speed pedal 133 to be unlocked, slidon a rail to a desired position, and locked in place; anelectromechanical system comprising an actuator that can be activated tocause the steering column 144 and/or the speed pedal 133 toautomatically move to a desired position; etc.).

The operator cabin 20 thus allows a user of the tracked utility vehicle10, who may be the operator or another user (e.g., an owner of thevehicle 10 or an employee of an entity owning the vehicle 10), to selecta desired one of the one-person cabin configuration and the two-personcabin configuration and readily configure the operator cabin 20 in thatselected configuration. This can enhance a versatility of the vehicle 10depending on an application or environment in which it is used.

While in this embodiment the plurality of cabin configurations in whichthe operator cabin 20 can be configured include the one-person cabinconfiguration and the two-person cabin configuration, in otherembodiments, the plurality of cabin configurations in which the operatorcabin 20 can be configured may include any number of different cabinconfigurations. For example, in other embodiments, the plurality ofcabin configurations in which the operator cabin 20 can be configuredmay include two (2) or more one-person cabin configurations that aredifferent from one another, and may or may not include a two-personcabin configuration. For instance, in some embodiments, the operatorcabin 20 may be configured in a first one-person cabin configuration inwhich the operator seat 150 is in a first operator seat position (e.g.,the operator seat position 176 in the cabin configuration shown in FIG.41) and in a second one-person cabin configuration in which the operatorseat 150 is in a second operator seat position different from the firstoperator seat position (e.g., the operator seat position 177 in thecabin configuration shown in FIG. 43), without including the passengerseat 152. This may allow the operator of the vehicle 10 to sit andoperate the vehicle 10 in different positions in the operator cabin 20depending on a need or preference of the operator and/or an applicationor environment in which the vehicle 10 is used.

The operator cabin 20, including the user interface 130 and the seatingarea 132, may be constructed in various other ways in other embodiments.For example, in other embodiments, the operator cabin 20 may not beconfigurable in different cabin configurations, but may rather have onlya single cabin configuration. For instance, in some cases, the operatorcabin 20 may always comprise only the operator seat 150, i.e., alwayshave a one-person cabin configuration, or both the operator seat 150 andthe passenger seat 152, i.e., always have a two-person cabinconfiguration.

d) Chassis

The chassis 12 comprises a frame 15 extending along the longitudinalaxis 59 of the tracked utility vehicle 10 and supporting variouscomponents of the vehicle 10, including the power plant 14, the trackassemblies 16 ₁, 16 ₂, and the operator cabin 20. The frame 15 alsosupports the work equipment 41 carried by the vehicle 10.

As further discussed below, in this embodiment, the frame 15 is“truck-like” in that at least part of it is configured like a truckframe. This enables the work equipment 41 to be mounted to the frame 15like on a truck frame. In particular, the frame 15 is configured suchthat the work equipment 41 can be supported on an area like thatstandardly supporting such work equipment in truck frames and can besecured to the frame 15 using attachment devices (e.g., attachmentplates or attachment threaded rod assemblies) standardly used forsecuring such work equipment to truck frames. As a result, workequipment such as the work equipment 41 may be as easily installable onthe tracked utility vehicle 10 as on trucks. Work equipment such as thework equipment 41 which may be primarily designed for trucks due to apotentially larger market for trucks can therefore also be easilyinstalled on the tracked utility vehicle 10.

With additional reference to FIGS. 19 to 25, in this embodiment, theframe 15 comprises an upper frame structure 60 and a lower framestructure 62.

The upper frame structure 60 is that portion of the frame 15 on whichrests and to which is secured the work equipment 41 carried by thetracked utility vehicle 10. To that end, the upper frame structure 60includes an equipment mounting area 99 for mounting the work equipment41 above the frame 15. In this embodiment, the upper frame structure 60comprises a pair of side rails 64 ₁, 64 ₂ extending along thelongitudinal direction of the vehicle 10 and spaced apart in thewidthwise direction of the vehicle 10. The upper frame structure 60 alsocomprises a plurality of crossmembers 66 ₁, 66 ₂ extending transversallyto the longitudinal direction of the vehicle 10 between the side rails64 ₁, 64 ₂. The upper frame structure 60 can thus be viewed as being atype of “ladder frame” construction.

In this embodiment, each side rail 64 _(i) is a C-shaped channelincluding a web 68 extending between a top flange 70 ₁ and a bottomflange 70 ₂. The side rail 64 _(i) is made of metallic material, in thiscase steel. The side rail 64 _(i) is dimensioned such that the siderails 64 ₁, 64 ₂ are able to support the work equipment 41. For example,in some examples of implementation: the web 68 may have a height H_(w)of at least 10 inches, in some cases at least 14 inches, and in somecases at least 18 inches and/or a thickness T_(w) of at least ¼ inches,in some cases at least ⅝ inches, and in some cases at least 1 inch;and/or each of the flanges 70 ₁, 70 ₂ may have a width W_(f) of at least2 inches, in some cases at least 5 inches, and in some cases at least 8inches and/or a thickness T_(f) of at least ¼ inches, in some cases atleast ⅝ inches, and in some cases at least 1 inch. In this example, theside rail 64 _(i) is made by bending a metallic plate to give it itsC-shape cross-section. Dimensions of the side rails 64 ₁, 64 ₂ may takeon various other values in other embodiments.

The side rails 64 ₁, 64 ₂ may be configured in various other ways inother embodiments. For example, in some embodiments, each of the siderails 64 ₁, 64 ₂ may be: a channel having a cross-sectional shape otherthan a C-shape (e.g., a U-shape); a hollow beam (e.g., a rectangular boxbeam); or any other suitable elongated structural member. As anotherexample, in some embodiments, the side rails 64 ₁, 64 ₂ may be made ofmaterial other than steel.

The crossmembers 66 ₁, 66 ₂ are secured to the side rails 64 ₁, 64 ₂ tointerconnect the side rails 64 ₁, 64 ₂. More particularly, in thisembodiment, fasteners (e.g., bolts and/or rivets) secure thecrossmembers 66 ₁, 66 ₂ to the side rails 64 ₁, 64 ₂. In otherembodiments, the crossmembers 66 ₁, 66 ₂ may be secured to the siderails 64 ₁, 64 ₂ in other ways (e.g., by welding). Also, in thisembodiment, the crossmember 66 ₁ is connected to the side rails 64 ₁, 64₂, while the crossmember 66 ₂ is connected to extension rail members 65₁, 65 ₂ that are secured to the side rails 64 ₄, 64 ₂. In this case, theextension rail members 65 ₁, 65 ₂ are C-shape channels fitted within theC-shape channels 64 ₁, 64 ₂.

In this embodiment, each crossmember 66 _(i) is a channel-like elongatedstructural member including a web 72 extending between a top flange 74₁, a bottom flange 74 ₂, and opposite end flanges 74 ₃, 74 ₄. Thecrossmember 66 _(i) is made of metallic material, in this case steel. Aplurality of openings 76 ₁-76 ₅ are provided in the web 72 for passingcables (e.g., hydraulic cables and/or electric cables) connected tocomponents of the vehicle 10 and/or the work equipment 41.

The crossmembers 66 ₁, 66 ₂ may be configured in various other ways inother embodiments. For example, in some embodiments, each of thecrossmembers 66 ₁, 66 ₂ may be a hollow beam (e.g., a rectangular boxbeam) or any other suitable elongated structural member. As anotherexample, in some embodiments, the crossmembers 66 ₁, 66 ₂ may be made ofmaterial other than steel.

A spacing S_(r) of the side rails 64 ₁, 64 ₂ in the widthwise directionof the tracked utility vehicle 10 may take on various values. In thisembodiment, the spacing S_(r) of the side rails 64 ₁, 64 ₂ correspondsto a standard truck frame side rail spacing. The “standard truck frameside rail spacing” refers to an industry-standard spacing of side railsof a frame of a truck chassis for trucks with a gross vehicle weightrating (GVWR) over 14000 lbs (6351 kg). A truck's GVWR corresponds to acurb weight of the truck plus a cargo and passenger weight capacity ofthe truck. In the United States, a GVWR over 14000 lbs would be a class4 or higher class according to the U.S. Department of Transportation'struck classification. A truck frame side rail spacing is considered tobe “standard” if a majority of truck models with a GVWR rating over14000 lbs sold by truck manufacturers in a given year in the countrywhere the tracked utility vehicle 10 is manufactured and/or used havethat truck frame side rail spacing.

For example, in this embodiment, the standard truck frame side railspacing is 34 inches and thus the spacing S_(r) of the side rails 64 ₁,64 ₂ is 34 inches. This may useful, for instance, in cases where thevehicle 10 is manufactured or used in the United States. The standardtruck frame side rail spacing, and thus the spacing S_(r) of the siderails 64 ₁, 64 ₂, may take on other values in other embodiments (e.g.,30 inches in Europe).

In other embodiments, the spacing S_(r) of the side rails 64 ₁, 64 ₂ maynot correspond to a standard truck frame side rail spacing, but may beselected taking into account truck frame side rail spacings. Forexample, in some embodiments, the spacing S_(r) of the side rails 64 ₁,64 ₂ may be no greater than 34 inches (about 0.86 m). For instance, insome embodiments, the spacing S_(r) of the side rails 64 ₁, 64 ₂ may bebetween 30 inches and 34 inches, in some cases between 32 inches and 34inches, and in some cases between 33 inches and 34 inches.

In yet other embodiments, the spacing S_(r) of the side rails 64 ₁, 64 ₂may be selected without considering any truck frame side rail spacing,and can thus have any suitable value.

The lower frame structure 62 is disposed below the upper frame structure60 and provides a main structure for supporting the track assemblies 16₁, 16 ₂. In this embodiment, the lower frame structure 62 is more rigidthan the upper frame structure 60. In this case, the lower framestructure 62 is the most rigid portion of the frame 15 and providestorsional ridigity. In this embodiment, the lower frame structure 62comprises a pair of side beams 80 ₁, 80 ₂ extending along thelongitudinal direction of the tracked utility vehicle 10 and spacedapart in the widthwise direction of the vehicle 10. The tower framestructure 62 also comprises a plurality of crossmembers 82 ₁-82 ₅extending transversally to the longitudinal direction of the vehicle 10between the side beams 80 ₁, 80 ₂. The lower frame structure 62 can thusalso be viewed as being a type of “ladder frame” construction. The lowerframe structure 62 also comprises a base plate 81 extending between theside beams 80 ₁, 80 ₂ to protect a fuel tank. The lower frame structure62 also comprises a front drawbar 87 ₁ and a rear drawbar 87 ₂.

In this embodiment, each of the side beams 80 ₁, 80 ₂ is a rectangularbox beam made of metallic material, in this case steel. The side beams80 ₁, 80 ₂ may be configured in various other ways in other embodiments.For example, in some embodiments, each of the side beams 80 ₁, 80 ₂ maybe: a hollow beam having a cross-sectional shape other than rectangular(e.g., circular or otherwise curved); a channel having a C-shape,U-shape or other suitable shape; or any other suitable elongatedstructural member. As another example, in some embodiments, the sidebeams 80 ₁, 80 ₂ may be made of material other than steel.

The crossmembers 82 ₁-82 ₅ are secured to the side beams 80 ₁, 80 ₂ tointerconnect the side beams 80 ₁, 80 ₂. More particularly, in thisembodiment, the crossmembers 82 ₁-82 ₅ are secured to the side beams 80₁, 80 ₂ by welding. The crossmembers 82 ₁-82 ₅ may be secured to theside beams 80 ₁, 80 ₂ in other ways in other embodiments (e.g., byfasteners such as bolts and/or rivets).

In this embodiment, the frame 15 defines an internal space 86. Thisinternal space 86, which will be referred to as a “tub”, can be used toreceive components of the tracked utility vehicle 10 and/or part of thework equipment 41 carried by the tracked utility vehicle 10 (e.g., thevehicle's fuel tank, pipes, cables, a dump box's hydraulic cylinder, acrane's torque box, etc.).

As shown in FIG. 20, in this embodiment, the frame 15 defines a verticalgap 78 between the upper frame structure 60 and the lower framestructure 62. The vertical gap 78 may facilitate use of attachmentthreaded rod assemblies or other attachment devices for attaching thework equipment 41 to the frame 15, as further discussed later on. Forexample, in some embodiments, the vertical gap 78 may have a heightH_(g) in the height direction of the tracked utility vehicle 10 of atleast 0.5 inches, in some cases at least 0.75 inches, in some cases atleast inch, in some cases 1.25 inches, and even more in some cases(e.g., 2 inches or more). In other embodiments, the upper framestructure 60 and the lower frame structure 62 may be contiguous suchthat there is no such vertical gap between them.

The track assemblies 16 ₁, 16 ₂ are mounted to the frame 15. In thisembodiment, the track assemblies 16 ₁, 16 ₂ are mounted to both thelower frame structure 62 and the upper frame structure 60. Moreparticularly, in this embodiment, each of the wheel mounting structures88 ₁-88 ₄ is secured to both the lower frame structure 62 and the upperframe structure 60. In this case, each of the wheel mounting structures88 ₁-88 ₄ is welded to the side beams 80 ₁, 86 ₂ of the lower framestructure 62 and fastened to the side rails 64 ₁, 64 ₂ of the upperframe structure 60 by fasteners (e.g., bolts and/or rivets). In othercases, each of the wheel mounting structures 88 ₁-88 ₄ may be fastenedto the side beams 80 ₁, 80 ₂ of the lower frame structure 62 byfasteners (e.g., bolts and/or rivets) and/or welded to the side rails 64₁, 64 ₂ of the upper frame structure 60. In this embodiment, the supportwheel mounting structures 88 ₂, 88 ₃ are also welded to the crossmembers82 ₁, 82 ₄.

The work equipment 41 is mounted to the frame 15. In this embodiment,the work equipment 41 is mounted to the upper frame structure 60. Moreparticularly, in this embodiment, the work equipment 41 rests on and issecured to the side rails 64 ₁, 64 ₂. Since the side rails 64 ₁, 64 ₂are C-shape channels standardly used in truck frames and since thespacing S_(r) of the side rails 64 ₁, 64 ₂ corresponds to the standardtruck frame side rail spacing, work equipment such as the work equipment41 may be as easily installable on the tracked utility vehicle 10 as ontrucks, even if it was primarily designed for trucks.

With additional reference to FIGS. 26 to 28, in this embodiment, a base90 of the work equipment 41 rests on the side rails 64 ₁, 64 ₂ of theframe 15. The base 90 of the work equipment 41 is secured to the siderails 64 ₁, 64 ₂ by a plurality of attachment devices 92 ₁-92 _(R), 94₁-94 _(P). For example, in this embodiment, each of the attachmentdevices 92 ₁-92 _(R) includes an attachment threaded rod assembly, andeach of the attachment devices 94 ₁-94 _(P) includes an attachmentplate. Such attachment threaded rod assemblies and attachment plates arestandardly used for securing work equipment such as the work equipment41 to trucks.

Each attachment threaded rod assembly 92 _(i) includes a pair ofthreaded rods 95 ₁, 95 ₂ and a bottom link 96 disposed around the siderail 64 _(i). The side rail 64 ₁ is located between the threaded rods 95₁, 95 ₂ which are secured to the bottom link 96 and an attachment part95 of the base 90 of the work equipment 41 with fasteners (e.g., nuts)to clamp the side rail 64 _(i). In this embodiment, the vertical gap 78between the side rail 64 _(i) and the side beam 80 ₁ facilitatesinstallation of the attachment threaded rod assembly 92 _(i). Inparticular, the gap 78 facilitates positioning of the bottom link 96beneath the side rail 64 and tightening of the fasteners on the threadedrods 95 ₁, 95 ₂.

Each attachment plate 94 _(i) is secured to the side rail 64 _(i) and tothe base 90 of the work equipment 41. More particularly, in thisembodiment, the attachment plate 94 _(i) is fastened to the web 68 ofthe side rail 64 _(i) by fasteners (e.g., bolts and/or rivets) andwelded to the base 90 of the work equipment 41. This type of attachmentplate can sometimes be referred to as a “fish plate”. The attachmentplate 94 _(i) may be secured to the side rail 64 _(i) and to the base 90of the work equipment 41 in other ways in other embodiments (e.g., bybeing fastened to the base 90 of the work equipment and/or welded to theside rail 64 _(i)).

In this example of implementation, the attachment plate 94 _(i) includesa generally rectangular lower part 51 fastened to the side rail 64 _(i)and a curved, in this case generally semicircular, upper part 53 weldedto the base 90 of the work equipment 41. The upper part 53 of theattachment plate 94 _(i) includes an opening 55, which may allow agreater length of weld bead when the attachment plate 94 _(i) is weldedto the base 90 of the work equipment 41. The attachment plate 94 _(i)may have various other shapes in other examples of implementation.

Although in this embodiment the attachment devices 92 ₁-92 _(R), 94 ₁-94_(P) securing the work equipment 41 to the frame 15 are attachmentthreaded rod assemblies and attachment plates, various other types ofattachment devices may be used in other embodiments.

While in embodiments considered above the tracked vehicle 10 is atracked carrier vehicle carrying work equipment, in other embodiments,certain features (e.g., the track tensioner 85 connected to thehydraulic drive system 21) of the tracked vehicle 10 may be implementedin other types of industrial tracked vehicles, such as an agriculturalvehicle (e.g., a tractor, a harvester, etc.) or a construction vehicle(e.g., a loader, a bulldozer, an excavator, etc.).

Any feature of any embodiment discussed herein may be combined with anyfeature of any other embodiment discussed herein in some examples ofimplementation.

Although various embodiments have been illustrated, this was for thepurpose of describing, but not limiting, the invention. Variousmodifications will become apparent to those skilled in the art and arewithin the scope of this invention, which is defined by the followingclaims.

The invention claimed is:
 1. A tracked vehicle comprising: a) a chassiscomprising a frame extending along a longitudinal direction of thetracked vehicle; b) an operator cabin mounted to the frame, the framecomprising a pair of side members extending in an area behind theoperator cabin in the longitudinal direction of the tracked vehicle, thepair of side members being spaced apart in a widthwise direction of thetracked vehicle for supporting work equipment carried by the trackedvehicle; c) a power plant mounted to the frame and comprising a primemover; and d) a plurality of track assemblies for traction of thetracked vehicle, a first one of the track assemblies being on a firstside of the tracked vehicle, a second one of the track assemblies beingon a second side of the tracked vehicle, each track assembly of theplurality of track assemblies being mounted to the frame and comprising:i) a plurality of wheels including: a drive wheel; an end wheel spacedapart from the drive wheel in the longitudinal direction of the trackedvehicle; and a plurality of support wheels arranged in an inlineconfiguration between the drive wheel and the end wheel; wherein atleast one of the support wheels comprises an inboard support wheelmember connected to an outboard support wheel member, the inboard andoutboard support wheel members defining a guiding space therebetween;wherein the end wheel and a particular one of the support wheels overlapin the longitudinal direction of the tracked vehicle; wherein theparticular one of the support wheels is at an end of the inlineconfiguration of the support wheels;  and ii) an endless track disposedaround the plurality of wheels for engaging the ground, the endlesstrack comprising: I. a top run extending between the drive wheel and theend wheel over the support wheels; II. a ground-engaging bottom runextending under the support wheels, the drive wheel being in drivingengagement with the endless track to impart motion to the endless track;and III. a wheel guide configured to pass through the guiding space ofthe at least one support wheel as the endless track moves around theplurality of wheels; wherein for each of the track assemblies, the endwheel is at least partly within the guiding space of the particular oneof the support wheels.
 2. The tracked vehicle defined in claim 1,wherein, for each of the track assemblies, the distance between a centerof rotation of the end wheel and a center of rotation of one of thesupport wheels is less than a sum of the radius of the end wheel and theradius of the one of the support wheels.
 3. The tracked vehicle definedin claim 1, wherein the operator's cabin is off-center along thewidthwise direction of the tracked vehicle.
 4. The tracked vehicledefined in claim 1, wherein the side members extend beyond the trackassemblies both frontwards and rearwards of the tracked vehicle.
 5. Thetracked vehicle defined in claim 1, wherein the operator's cabin and thepower plant are mounted above the frame.
 6. The tracked vehicle definedin claim 1, wherein the side members comprise side rails.
 7. The trackedvehicle defined in claim 1, wherein each of the endless tracks is ametal-embedded rubber track (MERT).
 8. The tracked vehicle defined inclaim 1, wherein the operator cabin comprises a floor, wherein anentirety of the floor is at a higher elevation, with respect to thebottom run of each of the track assemblies, than the uppermost surfaceof each of the side members, wherein the operator cabin extends in thelongitudinal direction, and wherein each of the side members extends inthe longitudinal direction past the operator cabin.
 9. The trackedvehicle defined in claim 1, wherein at least part of the operator cabinis located directly above at least part of one of the track assemblies.10. The tracked vehicle defined in claim 1, wherein the power plantcomprises an internal combustion engine, wherein an entirety of theinternal combustion engine is at a higher elevation, with respect to thebottom run of each of the track assemblies, than the uppermost surfaceof each of the side members, and wherein at least a portion of theinternal combustion engine overlies at least a portion of at least oneof the track assemblies.
 11. The tracked vehicle defined in claim 10,wherein a portion of the internal combustion engine that overlies the atleast a portion of at least one of the track assemblies is located in anarea rearwards of the operator cabin in the longitudinal direction. 12.The tracked vehicle defined in claim 10, further comprising a housing ontwo sides of the operator cabin, the housing covering the internalcombustion engine.
 13. The tracked vehicle defined in claim 12, whereinthe housing is L-shaped when viewed from above the tracked vehicle. 14.A tracked vehicle comprising: a) a chassis comprising a frame extendingalong a longitudinal direction of the tracked vehicle; b) an operatorcabin mounted to the frame and located entirely within a front half ofthe tracked vehicle, the frame comprising a pair of side membersextending in an area behind the operator cabin in the longitudinaldirection of the tracked vehicle, the pair of side members being spacedapart in a widthwise direction of the tracked vehicle for supportingwork equipment carried by the tracked vehicle; c) a power plant mountedto the frame and comprising a prime mover; and d) a plurality of trackassemblies for traction of the tracked vehicle, a first one of the trackassemblies being on a first side of the tracked vehicle, a second one ofthe track assemblies being on a second side of the tracked vehicle, eachtrack assembly of the plurality of track assemblies being mounted to theframe and comprising: i) a plurality of wheels including: a first wheelat a first end and a wheel at a second end spaced apart from the firstwheel in the longitudinal direction of the tracked vehicle; and aplurality of support wheels arranged in an inline configuration betweenthe first wheel and the second wheel; at least the first wheel and aparticular one of the support wheels overlapping in the longitudinaldirection of the tracked vehicle; wherein the particular one of thesupport wheels comprises an inboard support wheel member connected to anoutboard support wheel member, the inboard and outboard support wheelmembers defining a guiding space therebetween;  and ii) an endless trackdisposed around the plurality of wheels for engaging the ground, theendless track comprising: I. a top run extending between the first wheeland the second wheel over the support wheels; and II. a ground-engagingbottom run extending under the support wheels, one of the first wheeland the second wheel being in driving engagement with the endless trackto impart motion to the endless track; and III. a wheel guide configuredto pass through the guiding space of the at least one support wheel asthe endless track moves around the plurality of wheels; wherein for eachof the track assemblies, the first wheel is at least partly within theguiding space of the particular one of the support wheels.
 15. Thetracked vehicle defined in claim 14, wherein a front of one of the trackassemblies ends at a point directly underneath the operator cabin. 16.The tracked vehicle defined in claim 15, wherein the operator's cabin isoff-center along the widthwise direction of the tracked vehicle.
 17. Thetracked vehicle defined in claim 16, wherein the cabin and the powerplant are mounted above the operator's frame.
 18. The tracked vehicledefined in claim 14, wherein the first wheel of each of the trackassemblies is an idler wheel.
 19. The tracked vehicle defined in claim14, wherein the first wheel of each of the track assemblies is a drivewheel.
 20. The tracked vehicle defined in claim 14, wherein the firstwheel of each of the track assemblies is furthest to the rear of theplurality of wheels.
 21. The tracked vehicle defined in claim 14,wherein, for each of the track assemblies, the distance between a centerof rotation of the first wheel and a center of rotation of one of thesupport wheels is less than a sum of the radius of the first wheel andthe radius of the one of the support wheels with which it overlaps. 22.The tracked vehicle defined in claim 14, wherein the side members extendbeyond the track assemblies frontwards or rearwards of the trackedvehicle.
 23. The tracked vehicle defined in claim 22, wherein the sidemembers comprise side rails.
 24. The tracked vehicle defined in claim14, wherein each of the endless tracks is a metal-embedded rubber track(MERT).
 25. The tracked vehicle defined in claim 14, wherein theoperator cabin comprises a floor, wherein an entirety of the floor is ata higher elevation, with respect to the bottom run of each of the trackassemblies, than the uppermost surface of each of the side members,wherein the operator cabin extends in the longitudinal direction, andwherein each of the side members extends in the longitudinal directionpast the operator cabin.
 26. The tracked vehicle defined in claim 14,wherein at least part of the operator cabin is located directly above atleast part of one of the track assemblies.
 27. The tracked vehicledefined in claim 14, wherein the power plant comprises an internalcombustion engine, wherein an entirety of the internal combustion engineis at a higher elevation, with respect to the bottom run of each of thetrack assemblies, than the uppermost surface of each of the sidemembers, and wherein at least a portion of the internal combustionengine overlies at least a portion of at least one of the trackassemblies.
 28. The tracked vehicle defined in claim 27, wherein aportion of the internal combustion engine that overlies the at least aportion of at least one of the track assemblies is located in an arearearwards of the operator cabin in the longitudinal direction.
 29. Thetracked vehicle defined in claim 27, further comprising a housing on twosides of the operator cabin, the housing covering the internalcombustion engine.
 30. The tracked vehicle defined in claim 29, whereinthe housing is L-shaped when viewed from above the tracked vehicle.